U.S. patent application number 15/903352 was filed with the patent office on 2018-06-28 for utilizing a plurality of uplink carriers and a plurality of downlink carriers for multi-cell communications.
This patent application is currently assigned to InterDigital Patent Holdings, Inc.. The applicant listed for this patent is InterDigital Patent Holdings, Inc.. Invention is credited to Christopher R. Cave, Paul Marinier, Diana Pani, Benoit Pelletier.
Application Number | 20180184284 15/903352 |
Document ID | / |
Family ID | 41561239 |
Filed Date | 2018-06-28 |
United States Patent
Application |
20180184284 |
Kind Code |
A1 |
Cave; Christopher R. ; et
al. |
June 28, 2018 |
UTILIZING A PLURALITY OF UPLINK CARRIERS AND A PLURALITY OF
DOWNLINK CARRIERS FOR MULTI-CELL COMMUNICATIONS
Abstract
A first message may be received on a first carrier and
communication initiated using a second carrier based on the
received first message. Communication may continue on the first
carrier such that the first carrier and the second carrier have
different radio network terminal identifiers (RNTIs) and the first
and second carrier have discontinuous reception cycles with
different times of discontinuous reception. The discontinuous
reception of the first carrier may be ceased based on a second
message and the discontinuous reception of the second carrier may
be ceased based on the third message.
Inventors: |
Cave; Christopher R.;
(Dollard-des-Ormeaux, CA) ; Pani; Diana;
(Montreal, CA) ; Pelletier; Benoit; (Roxboro,
CA) ; Marinier; Paul; (Brossard, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
InterDigital Patent Holdings, Inc. |
Wilmington |
DE |
US |
|
|
Assignee: |
InterDigital Patent Holdings,
Inc.
Wilmington
DE
|
Family ID: |
41561239 |
Appl. No.: |
15/903352 |
Filed: |
February 23, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14930241 |
Nov 2, 2015 |
9924350 |
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15903352 |
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12625845 |
Nov 25, 2009 |
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14930241 |
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61168750 |
Apr 13, 2009 |
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61141926 |
Dec 31, 2008 |
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61117854 |
Nov 25, 2008 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W 72/0446 20130101;
H04W 72/0453 20130101; H04W 76/28 20180201; H04W 48/12 20130101;
H04W 72/0406 20130101; H04W 72/02 20130101; H04W 28/0284 20130101;
H04W 52/44 20130101; H04W 8/26 20130101; H04W 28/26 20130101; H04W
28/021 20130101; H04L 5/0098 20130101; H04W 72/042 20130101 |
International
Class: |
H04W 8/26 20060101
H04W008/26; H04W 72/04 20060101 H04W072/04; H04W 28/02 20060101
H04W028/02; H04W 76/28 20060101 H04W076/28; H04L 5/00 20060101
H04L005/00; H04W 72/02 20060101 H04W072/02 |
Claims
1. A wireless transmit/receive unit (WTRU) comprising: a
transceiver; and a processor; and the transceiver configured to
receive a first message on a first carrier; and the processor and
the transceiver are configured to initiate communication using a
second carrier based on the received first message and to continue
to communicate on the first carrier, wherein the first carrier and
the second carrier have different radio network terminal
identifiers (RNTIs) and wherein the first and second carrier have
discontinuous reception cycles and the first and the second
carriers have different times of discontinuous reception; the
transceiver is configured to receive a second message based on a
first RNTI of the first carrier and to receive a third message
based on a second RNTI of the second carrier; and the transceiver
and the processor are configured to cease the discontinuous
reception of the first carrier based on the second message and to
cease the discontinuous reception of the second carrier based on
the third message.
2. The WTRU of claim 1 further comprising: the transceiver is
further configured to receive radio resource control signaling from
a base station configuring the second carrier.
3. The WTRU of claim 1, wherein the second message is a medium
access control (MAC) message that includes a bit map and a bit in
the bit map indicates whether at least one of a plurality of
carriers is activated or deactivated.
4. The WTRU of claim 1, wherein the first carrier and the second
carrier are part of LTE or LTE-A cells.
5. The WTRU of claim 1, wherein the first carrier and the second
carrier are part of W-CDMA cells.
6. The WTRU of claim 1, wherein the WTRU is configured to transmit
a physical control channel using the first carrier without
transmission of a control channel on the second carrier.
7. A method performed by a wireless transmit/receive unit (WTRU),
the method comprising: receiving, by the WTRU, a first message on a
first carrier; initiating, by the WTRU, communication using a
second carrier based on the received first message and to continue
to communicate on the first carrier, wherein the first carrier and
the second carrier have different radio network terminal
identifiers (RNTIs) and wherein the first and second carrier have
discontinuous reception cycles and the first and the second
carriers have different times of discontinuous reception;
receiving, by the WTRU, a second message based on a first RNTI of
the first carrier and receiving a third message based on a second
RNTI of the second carrier; and ceasing, by the WTRU, the
discontinuous reception of the first carrier based on the second
message and ceasing the discontinuous reception of the second
carrier based on the third message.
8. The method of claim 7 further comprising: receiving, by the
WTRU, radio resource control signaling from a base station
configuring the second carrier.
9. The method of claim 7, wherein the second message is a medium
access control (MAC) message that includes a bit map and a bit in
the bit map indicates whether at least one of a plurality of
carriers is activated or deactivated.
10. The method of claim 7, wherein the first carrier and the second
carrier are part of LTE or LTE-A cells.
11. The method of claim 7, wherein the first carrier and the second
carrier are part of W-CDMA cells.
12. The method of claim 7 further comprising: transmitting, by the
WTRU, a physical control channel using the first carrier without
transmission of a control channel on the second carrier.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 14/930,241, filed Nov. 2, 2015, which is a
continuation of U.S. patent application Ser. No. 12/625,845, filed
Nov. 25, 2009, which claims the benefit of U.S. provisional
application Nos. 61/117,854 filed Nov. 25, 2008, 61/141,926 filed
Dec. 31, 2008, and 61/168,750 filed Apr. 13, 2009, which are
incorporated by reference as if fully set forth herein.
FIELD OF INVENTION
[0002] This application is related to wireless communications.
BACKGROUND
[0003] Wireless communication systems keep evolving to meet the
needs for providing continuous and faster access to a data network.
In order to meet these needs, wireless communication systems may
use multiple carriers for the transmission of data. A wireless
communication system that uses multiple carriers for the
transmission of data may be referred to as a multi-carrier system.
The use of multiple carriers is expanding in both cellular and
non-cellular wireless systems.
[0004] A multi-carrier system may increase the bandwidth available
in a wireless communication system. For instance, a dual carrier
system may double the bandwidth when compared to a single carrier
system and a tri-carrier system may triple the bandwidth when
compared to a single carrier system, etc. In addition to this
throughput gain, diversity and joint scheduling gains may also be
achieved. This may result in improving the quality of service (QoS)
for end users. Further, the use of multiple carriers may be used in
combination with multiple-input multiple-output (MIMO).
[0005] By way of example, in the context of Third Generation
Partnership Project (3GPP) system, dual cell high speed downlink
packet access (DC-HSDPA) is included in Release 8 of the 3GPP
specifications. With DC-HSDPA, a base station (also referred to as
a Node-B) communicates with a wireless transmit/receive unit (WTRU)
over two downlink carriers simultaneously. This may double the
bandwidth and the peak data rate available to WTRUs and also has a
potential to increase the network efficiency by means of fast
scheduling and fast channel feedback over two carriers.
[0006] For DC-HSDPA operation, each WTRU may be assigned two
downlink carriers: an anchor carrier (primary carrier) and a
supplementary carrier (secondary carrier). The anchor carrier may
carry dedicated and shared control channels used for high speed
downlink shared channel (HS-DSCH), enhanced dedicated channel
(E-DCH), and dedicated channel (DCH) operations (e.g., fractional
dedicated physical channel (F-DPCH), E-DCH HARQ indicator channel
(E-HICH), E-DCH relative grant channel (E-RGCH), E-DCH absolute
grant channel (E-AGCH), common pilot channel (CPICH), high speed
shared control channel (HS-SCCH), and high speed physical downlink
shared channel (HS-PDSCH), and the like). The supplementary carrier
may carry the CPICH, HS-SCCH and HS-PDSCH for the WTRU. The uplink
transmission remains on a single carrier as in the current systems.
The high speed dedicated physical control channel (HS-DPCCH)
feedback information may be provided on the uplink carrier to the
Node-B and contains information for each downlink carrier.
[0007] FIG. 1 shows a medium access control (MAC) layer structure
for DC-HSDPA operation. The MAC-ehs entity includes one hybrid
automatic repeat request (HARQ) entity per HS-DSCH transport
channel. HARQ retransmissions may occur over the same transport
channel and thus may reduce the benefit of frequency diversity
potentially brought by the use of more than one carrier if each
HS-DSCH transport channel has a fixed mapping to physical channel
resources. However, it has been suggested that the mapping between
an HS-DSCH and physical resources (e.g., codes and carrier
frequencies) may be dynamically modified in order to provide a
diversity benefit.
[0008] Multi-carrier or multi-cell uplink transmissions may be
implemented in order to increase data rates and capacity in the
uplink. For example, the use of multi-cell uplink transmissions may
improve data processing and power consumption of the WTRU. However,
because multiple uplink carriers are continuously transmitting on
the uplink, even during the periods of inactivity, WTRU battery
life may significantly decrease. Additionally, continuous DPCCH
transmission on any secondary uplink carrier(s) may have a negative
impact on system capacity.
[0009] While continuous packet connectivity (CPC) operations are
implemented for single carrier uplink transmissions that help the
WTRU decrease power consumption while in CELL_DCH, methods and
apparatus for power control for multi-carrier uplink communications
are desired.
SUMMARY
[0010] A method and apparatus for utilizing a plurality of uplink
carriers and a plurality of downlink carriers are disclosed. A WTRU
activates a primary uplink carrier and a primary downlink carrier
and activates or deactivates a secondary uplink carrier based on an
order from a network or upon detection of a pre-configured
condition. The order may be a physical layer signal such as an
HS-SCCH order.
[0011] The WTRU may deactivate a secondary downlink carrier upon
deactivation of the secondary uplink carrier, or vice versa. The
WTRU may activate the secondary uplink carrier upon activation of
the secondary downlink carrier. The WTRU may deactivate/activate
the secondary uplink carrier upon discontinuous transmission (DTX)
activation/deactivation on the primary uplink carrier. The order
may be transmitted via an HS-SCCH order or an E-AGCH message. The
WTRU may deactivate the secondary uplink carrier based on
inactivity of the E-DCH transmission, a buffer status, a channel
condition, power constraints, or other similar triggers.
[0012] When the secondary uplink carrier is activated, DPCCH
transmission may be initiated a predetermined time period prior to
initiating the E-DCH transmissions on the secondary uplink carrier.
The initial DPCCH transmission power on the secondary uplink
carrier may be set based on a DPCCH transmission power on the
primary uplink carrier or may be set to a value signaled by a
network. A default grant value may be used for initial E-DCH
transmission on the secondary uplink carrier upon activation of the
secondary uplink carrier.
[0013] The same DTX status configured for the primary uplink
carrier may be used for the secondary uplink carrier upon
activation of the secondary uplink carrier. A DTX pattern for the
primary uplink carrier and the secondary uplink carrier may be
aligned or configured independently.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] A more detailed understanding may be had from the following
description, given by way of example in conjunction with the
accompanying drawings wherein:
[0015] FIG. 1 shows a MAC layer structure for DC-HSDPA
operation;
[0016] FIG. 2 shows an example wireless communication system;
[0017] FIG. 3 is a functional block diagram of an example WTRU and
an example Node-B of the wireless communication system of FIG.
2;
[0018] FIG. 4 shows an example WTRU configured to transmit two
uplink carriers to the UTRAN in accordance with one embodiment;
[0019] FIG. 5 shows an example WTRU configured to transmit two
uplink carriers to the UTRAN in accordance with another
embodiment;
[0020] FIG. 6 is a flow diagram showing dynamic carrier adjustment
in a WTRU;
[0021] FIG. 7 shows example transitions among various states of
carrier activation/deactivation in accordance with the HS-SCCH
orders;
[0022] FIG. 8 shows signaling of the indication of secondary uplink
carrier activation/deactivation using NBAP;
[0023] FIG. 9 shows signaling of the indication of secondary uplink
carrier activation/deactivation using NBAP and RNSAP;
[0024] FIG. 10 is a flow diagram showing a method for autonomous
dynamic carrier adjustment in a WTRU;
[0025] FIG. 11 is a flow diagram illustrating procedures associated
with deactivating a secondary uplink carrier; and
[0026] FIG. 12 is a flow diagram illustrating procedures associated
with activating a secondary uplink carrier.
DETAILED DESCRIPTION
[0027] When referred to hereafter, the terminology "WTRU" includes
but is not limited to a user equipment (UE), a mobile station, a
fixed or mobile subscriber unit, a pager, a cellular telephone, a
personal digital assistant (PDA), a computer, a machine-to-machine
(M2M) device, a sensor, or any other type of device capable of
operating in a wireless environment. When referred to hereafter,
the terminology "Node-B" includes but is not limited to a base
station, a site controller, an access point (AP), or any other type
of interfacing device capable of operating in a wireless
environment.
[0028] The network may assign at least one downlink and/or at least
one uplink carrier as an anchor downlink carrier and an anchor
uplink carrier, respectively. In multi-carrier operation a WTRU may
be configured to operate with two or more carriers (also referred
to as frequencies). Each of these carriers may have distinct
characteristics and logical association with the network and the
WTRU, and the operating frequencies may be grouped and referred to
as anchor (or primary) carrier and supplementary (or secondary)
carrier. Hereinafter, the terminologies "anchor carrier" and
"primary carrier", and "supplementary carrier" and "secondary
carrier" may be used interchangeably, respectively. If more than
two carriers are configured the WTRU may contain more than one
primary carrier and/or more than one secondary carrier(s). The
embodiments described herein are applicable and may be extended to
these scenarios as well. For example, the anchor carrier may be
defined as the carrier for carrying a specific set of control
information for downlink/uplink transmissions. Any carrier that is
not assigned as an anchor carrier may be a supplementary carrier.
Alternatively, the network may not assign an anchor carrier and no
priority, preference, or default status may be given to any
downlink or uplink carriers. For multi-carrier operation more than
one supplementary carriers or secondary carriers may exist.
[0029] FIG. 2 shows an example wireless communication system 100
including a plurality of WTRUs 110, a Node-B 120, a controlling
radio network controller (CRNC) 130, a serving radio network
controller (SRNC) 140, and a core network 150. The Node-B 120 and
the CRNC 130 with the SRNC 140 may collectively be referred to as
the UTRAN.
[0030] As shown in FIG. 2, the WTRUs 110 are in communication with
the Node-B 120, which is in communication with the CRNC 130 and the
SRNC 140. The communication between the WTRU 110 and the Node-B 120
may be performed via a plurality of downlink carriers (e.g., at
least one primary downlink carrier and at least one secondary
downlink carrier) and a plurality of uplink carriers (e.g., at
least one primary uplink carrier and at least one secondary uplink
carrier). Although three WTRUs 110, one Node-B 120, one CRNC 130,
and one SRNC 140 are shown in FIG. 2, it should be noted that any
combination of wireless and wired devices may be included in the
wireless communication system 100.
[0031] FIG. 3 is a functional block diagram of a WTRU 110 and the
Node-B 120 of the wireless communication system 100 of FIG. 2. As
shown in FIG. 3, the WTRU 110 is in communication with the Node-B
120 and both are configured to perform a method of performing
uplink transmissions with multiple uplink carriers. The WTRU 110
includes a processor 115, a receiver 116, a transmitter 117, a
memory 118, an antenna 119, and other components (not shown) that
may be found in a typical WTRU. The memory 118 is provided to store
software including operating system, application, etc. The
processor 115 is provided to perform, alone or in association with
the software, a method of performing uplink transmissions with
multiple uplink carriers. The receiver 116 and the transmitter 117
are in communication with the processor 115. The receiver 116
and/or the transmitter 117 may be configured to receive and/or
transmit on multiple carriers simultaneously, respectively.
Alternatively, the WTRU 110 may include multiple receivers and/or
transmitters. The antenna 119 is in communication with both the
receiver 116 and the transmitter 117 to facilitate the transmission
and reception of wireless data.
[0032] The Node-B 120 includes a processor 125, a receiver 126, a
transmitter 127, an antenna 128, and other components (not shown)
that may be found in a typical base station. The processor 125 is
provided to perform, alone or in association with the software, a
method of performing uplink transmissions with multiple uplink
carriers. The receiver 126 and the transmitter 127 are in
communication with the processor 125. The receiver 126 and/or the
transmitter 127 may be configured to receive and/or transmit on
multiple carriers simultaneously, respectively. Alternatively, the
Node-B 120 may include multiple receivers and/or transmitters. The
antenna 128 is in communication with both the receiver 126 and the
transmitter 127 to facilitate the transmission and reception of
wireless data.
[0033] It should be noted that although the embodiments described
herein are described with reference to channels associated with
HSPA+, the embodiments are applicable to any other multi-carrier
systems (and the channels used therein) such as LTE Release 8 or
later, and LTE-Advanced, as well as any other type of wireless
communication systems, and the channels used therein. It should
also be noted that the embodiments described herein may be
applicable in any order or in any combination.
[0034] Embodiments for activation and deactivation of the secondary
uplink carrier and discontinuous transmission (DTX) on the
secondary uplink carrier are disclosed hereafter. The embodiments
described hereafter may be used individually or in combination with
other embodiments. It should be understood that even though the
embodiments disclosed below are described in terms of two uplink
carriers (one primary carrier and one secondary carrier), the
embodiments may be extended to any number of uplink carriers. The
secondary uplink carrier may be referred to as the secondary
serving enhanced dedicated channel (E-DCH) cell. The secondary
downlink carrier may be referred to as the secondary HS-DSCH
serving cell.
[0035] FIG. 4 shows an example WTRU configured to transmit multiple
uplink carriers to the UTRAN in accordance with one embodiment. The
WTRU 110 may transmit a data channel(s), (e.g., E-DCH dedicated
physical data channel (E-DPDCH)), and pilot and other control
channels, (e.g., DPCCH, E-DCH dedicated physical control channel
(E-DPCCH), and/or HS-DSCH dedicated physical control channel
(HS-DPCCH)), on the anchor uplink carrier, and transmit a data
channel (e.g., E-DPDCH) and a pilot channel on the supplementary
uplink carrier.
[0036] The anchor uplink carrier may carry all or most of the
uplink control signaling that is sent to the UTRAN. Examples of
control signaling may include, but are not limited to: (1) feedback
for downlink channels (such as HS-DPDCH) including channel quality
information (CQI), precoding control indication (PCI), ACK/NACK
HARQ information; (2) uplink radio link control information, (e.g.,
uplink DPCCH), including uplink pilot symbols, feedback information
(FBI), and transmission power control (TPC) commands; or (3) E-DCH
control information, (e.g., E-DPCCH), including retransmission
sequence number (RSN) used for HARQ processing, E-DCH transport
format combination index (E-TFCI) information indicating the size
of the transmitted transport blocks, and a happy bit. The data
channel, (e.g., E-DPDCH), may convey user traffic on the anchor
uplink carrier as illustrated in FIG. 4.
[0037] Alternatively, the secondary uplink carrier may also carry
the E-DCH control information that may be associated with the
transmission of the secondary uplink carrier, as shown in FIG. 5.
E-DCH control information transmitted on the anchor uplink carrier
may be related to the data transmission on the anchor uplink
carrier. A separate E-DPCCH may be sent on the secondary uplink
carrier for transmitting the E-DCH control information in addition
to the data and pilot channels (in a similar manner to single
carrier operation).
[0038] FIG. 6 is a flow diagram showing dynamic carrier adjustment
in a WTRU 110. The WTRU 110 may be configured to perform this
dynamic carrier adjustment as a part of a power control procedure,
to reduce data processing load in the WTRU 110, for traffic control
in a communication network, or other network defined or
predetermined reasons. As shown in FIG. 6, the WTRU 110 receives a
signal indicating to the WTRU 110 to activate or deactivate a
secondary carrier. In another alternative, the signal may indicate
to the WTRU 110 to adjust an operating characteristic of the
secondary carrier, such as transmit power adjustments, or DTX
pattern or cycle adjustments, or the like. The signal may be
explicitly signaled or implicitly signaled. Upon receiving the
signal, the WTRU 110 determines which carriers to activate,
deactivate, or modify and then performs the appropriate secondary
activation, deactivation, or modification procedures. This may
comprise accounting for ongoing or scheduled transmissions on the
carriers. Upon activating, deactivating or modifying the secondary
carriers, the WTRU 110 may then be configured to adjust the DTX
patterns. While the embodiments described address the controlling
the secondary carrier(s) it should be understood that the methods
described may be applied to anchor carrier(s) as well.
[0039] In accordance with one embodiment, the WTRU 110 may be
configured to receive an explicit signal notifying the WTRU 100 to
activate or deactivate secondary uplink carrier(s) from the
network. The explicit signaling may include, but is not limited to
layer 1 signaling (e.g., HS-SCCH orders, E-AGCH signals), layer 2
signaling (e.g., messages in a MAC-ehs protocol data unit (PDU),
E-RNTI, or MAC headers), or layer 3 signaling (e.g., RRC messages).
Based on the signaling, the WTRU 110 may activate or deactivate its
secondary carrier(s). By performing the dynamic control of the
secondary uplink carrier(s), the WTRU 110 may be able to save
transmission power.
[0040] In one embodiment, the network may explicitly signal the
WTRU 110 to activate or deactivate the secondary uplink carrier via
a conventional layer 1 signal, (e.g., a high speed shared control
channel (HS-SCCH) order), or a new layer 1 signal. For example, a
HS-SCCH order may be defined to activate or deactivate the
secondary uplink carrier. The HS-SCCH order may be sent via the
primary and/or secondary serving HS-DSCH cell. Upon reception of
the layer 1 signal, (e.g., HS-SCCH order), the WTRU 110 activates
or deactivates transmission on the secondary uplink carrier. The
reception of the HS-SCCH order may also act as an implicit
indication that the WTRU 110 stops monitoring the downlink control
signaling such as the E-HICH, E-RGCH, E-AGCH associated to the
secondary uplink carrier, if applicable. The HS-SCCH order may
optionally indicate that the WTRU 110 stops monitoring the
secondary downlink carrier.
[0041] The HS-SCCH order signal may comprise order type bits
X.sub.odt,1, X.sub.odt,2, X.sub.odt,3 and order bits X.sub.ord,1,
X.sub.ord,2, X.sub.ord,3. For example, if the order type bits
X.sub.odt,1, X.sub.odt,2, X.sub.odt,3=`001`, then the mapping for
X.sub.ord,1, X.sub.ord,2, X.sub.ord,3 may be defined as
follows:
[0042] X.sub.ord,1, X.sub.ord,2, X.sub.ord,3 may be comprised of:
[0043] Reserved (1 bits): X.sub.ord,1=X.sub.res,1 [0044] Secondary
serving E-DCH cell activation (1 bit):
x.sub.ord,2=X.sub.E-DCH.sub._.sub.secondary,1 [0045] Secondary
serving HS-DSCH cell activation (1 bit):
X.sub.ord,3=X.sub.secondary,1
[0046] If X.sub.E-DCH.sub._.sub.secondary,1=`0`l , then the HS-SCCH
order may be a secondary serving E-DCH cell de-activation
order;
[0047] If X.sub.E-DCH.sub._.sub.secondary,1=`1`, then the HS-SCCH
order may be a secondary serving E-DCH cell activation order;
[0048] If X.sub.secondary,1=`0`, then the HS-SCCH order may be a
secondary serving HS-DSCH cell de-activation order; and
[0049] If X.sub.secondary,1=`1`, then the HS-SCCH order may be a
secondary serving HS-DSCH cell activation order.
[0050] FIG. 7 shows example transitions among various states of
carrier activation/deactivation in accordance with the HS-SCCH
orders. An HS-SCCH order "000" makes the state transition to the
state in which both the secondary serving E-DCH cell and the
secondary HS-DSCH cell are deactivated. An HS-SCCH order "001"
makes the state transition to the state in which the secondary
serving E-DCH cell is deactivated and the secondary HS-DSCH cell is
activated. An HS-SCCH order "011" makes the state transition to a
state in which both the secondary serving E-DCH cell and the
secondary HS-DSCH cell are activated. A state in which the
secondary serving E-DCH cell is activated and the secondary HS-DSCH
cell is deactivated may be defined (not shown in FIG. 7) and an
HS-SCCH order "010" may be used to transition to that state.
[0051] Alternatively, a new order type may be defined for this
purpose. This alternative approach may be scalable to more than one
uplink carrier. For example, if order type bits X.sub.odt,1,
X.sub.odt,2, X.sub.odt,3=`010`, then the mapping for X.sub.ord,1,
X.sub.ord,2, X.sub.ord,3 may be defined as follows:
[0052] X.sub.ord,1, X.sub.ord,2, X.sub.ord,3 may be comprised of:
[0053] Reserved (2 bits): X.sub.ord,1, X.sub.ord,2=X.sub.res,1,
X.sub.res,2 [0054] Secondary serving E-DCH cell activation (1 bit):
X.sub.ord,3=X.sub.E-DCH.sub._.sub.secondary,1
[0055] If X.sub.E-DCH.sub._.sub.secondary,1=`0`, then the HS-SCCH
order may be a secondary serving E-DCH cell de-activation order;
and
[0056] If X.sub.E-DCH.sub._.sub.secondary,1=`1`, then the HS-SCCH
order may be a secondary serving E-DCH cell activation order.
[0057] In another embodiment, an order received by the WTRU 110 may
be used as explicit signaling to activate or deactivate any
secondary uplink carrier(s). For example, an HS-SCCH order used to
activate or deactivate the secondary downlink carrier may be used
for activating or deactivating the secondary uplink carrier. An
HS-SCCH order used to deactivate the secondary downlink carrier may
implicitly order the WTRU 110 to also deactivate the secondary
uplink carrier. Accordingly, when a secondary downlink carrier is
deactivated by the network, the WTRU 110 may also deactivate a
secondary uplink carrier. However, the HS-SCCH order to activate
the secondary downlink carrier may not implicitly activate the
secondary uplink carrier as well. Alternatively, the WTRU 110 may
be configured to activate the secondary uplink carrier with
secondary downlink carrier activation.
[0058] In another embodiment, the WTRU 110 may receive a DTX
activation order for the primary uplink carrier which may
implicitly deactivate the secondary uplink carrier. DTX
deactivation may reactivate the secondary uplink carrier.
Alternatively, an explicit activation order may be used to
reactivate the secondary uplink carrier.
[0059] In accordance with another embodiment, the E-AGCH may be
used to explicitly notify the WTRU 110 to deactivate or activate
the secondary uplink carrier. For instance, the Node-B 120 may use
the E-AGCH associated to the secondary uplink carrier, (or
alternatively the E-AGCH associated to the primary carrier), to
signal the absolute grant value set to `INACTIVE`, with the
absolute grant scope set to "all HARQ processes", or alternatively
the absolute grant value set to zero. Alternatively, a particular
absolute grant value or a combination of an absolute grant value
with an absolute grant scope may be reserved to signal deactivation
or activation of the secondary uplink carrier. Upon reception of
this absolute grant message the WTRU 110 deactivates the secondary
uplink carrier.
[0060] Alternatively, an additional field(s) may be added to the
absolute grant message. For example, this field may comprise one
bit to indicate to the WTRU 110 to activate or deactivate the
secondary uplink carrier. If this bit is set, the WTRU 110 may
deactivate the secondary uplink carrier. This may be signaled on
any of the E-AGCH used to control the scheduling for the primary
uplink carrier or the secondary uplink carrier. Optionally,
unsetting this bit on the E-AGCH for the primary uplink carrier
while the secondary uplink carrier is deactivated, may indicate to
the WTRU 110 to activate the secondary uplink carrier. In another
embodiment, multiple bits may be added to the absolute grant, each
bit corresponding to one or more supplementary carriers.
Alternatively, other methods described herein may be used to
activate the secondary uplink carrier.
[0061] Alternatively, a special value of the absolute grant value
field may be used to indicate deactivation or activation of the
secondary uplink carrier.
[0062] Alternatively, the absolute grant scope bit may be
re-interpreted to indicate activation or deactivation of the
secondary uplink carrier.
[0063] Alternatively, the WTRU 110 may use a layer 2 message to
deactivate or activate the secondary uplink carrier. The layer 2
message may be included in a MAC-ehs protocol data unit (PDU). For
example, a special value of the logical channel identity (LCH-ID)
field may be used to indicate the presence of this message,
optionally followed by four (4) spare bits, where two of the four
spare bits may be reserved to indicate activation or deactivation
of the secondary uplink carrier.
[0064] Alternatively, a separate E-RNTI may be allocated to the
WTRU and used to indicate deactivation or activation of the
secondary uplink carrier over the E-AGCH. If the secondary uplink
carrier is activated or deactivated, the E-AGCH may be masked with
the special E-RNTI. Upon detection of this E-AGCH with the special
E-RNTI, the WTRU 110 activates or deactivates the secondary uplink
carrier. The absolute grant value in this E-AGCH transmission may,
for instance, be set to "zero" or "inactive" when signaling a
deactivation order. When re-enabling the secondary uplink carrier,
the absolute grant value of this E-AGCH transmission may be set to
the value the network assigns the WTRU 110 to use for initial E-DCH
transmission when the secondary uplink carrier is activated.
[0065] An indication to deactivate or activate the secondary uplink
carrier(s) using layer 1 or layer 2 signaling may originate from
the serving Node-B 120. Since other Node-Bs in the active set of
the WTRU 110 may also be monitoring the secondary uplink channel
from the WTRU, the other Node-Bs would benefit from an indication
that the WTRU 110 may be deactivating or activating the secondary
uplink carrier(s). The indication of the deactivation or activation
may be an acknowledgment of the deactivation or activation order
from the network, or indication of the WTRU-initiated or
WTRU-assisted deactivation or activation. In accordance with one
embodiment, the WTRU 110 may send an indication in the uplink that
the secondary uplink carrier(s) is deactivated or activated.
[0066] The indication may be realized in any of the following ways.
A special or reserved value of the E-DCH transport format
combination index (E-TFCI) may be transmitted in the uplink via the
E-DPCCH. The WTRU 110 may send the special E-TFCI when there is no
data to transmit on the corresponding uplink carrier, (i.e.,
E-DPDCH is not transmitted).
[0067] Alternatively, the happy bit of the E-DPCCH in the secondary
uplink carrier may be used to signal this indication. The happy bit
may be implemented as a flag related to a rate request on a control
channel (e.g., E-DPCCH) and the scheduling information (SI). The
happy-bit may be transmitted in-band (e.g., on the E-DCH). The
happy bit may be re-used and re-interpreted to indicate the
deactivation or activation of the secondary uplink carrier. For
example, a happy bit sent on a channel of the secondary uplink
carrier (e.g., E-DPCCH) may indicate to other Node-Bs that the
secondary carrier may be deactivated, rather than indicating a
state of happiness, since the indication of happiness may be sent
over the anchor carrier, or alternatively another secondary
carrier. In multi-carrier systems with more than two carriers, one
or more happy bits may be used.
[0068] Alternatively, a special value of the scheduling information
(SI) may be used to indicate that the WTRU 110 has deactivated, or
is going to deactivate, the secondary uplink carrier. For instance,
the value of total E-DCH buffer status (TEBS) set to zero may be
used to report implicit deactivation of the secondary uplink
carrier. Alternatively, the WTRU 110 may use power headroom of zero
to indicate implicit deactivation of the secondary uplink carrier.
If two power headroom fields are present in the SI field, the WTRU
110 may report power headroom of zero for the secondary uplink
carrier. Alternatively, a TEBS value that may be lower than a
pre-configured threshold may also signal the deactivation of the
secondary uplink carrier. Alternatively, a special reserved value
of the highest logical channel identity (HLID) or highest priority
logical channel buffer status (HLBS) may be used to indicate
deactivation or activation of the secondary uplink carrier.
[0069] Alternatively, layer 2 signaling in the MAC-i header using
the special value of the LCH-ID field and using, for example, one
or two values of the four spare bits may be used to indicate the
deactivation of the secondary uplink carrier.
[0070] Alternatively, the serving Node-B 120 may signal to all
cells in the active set that the secondary uplink carrier has been
deactivated or may be deactivated a number of TTIs from the
transmission of the indication. By way of example, the signaling
procedures for indicating that the secondary uplink carrier has
been deactivated or activated may be realized using Node-B
application part (NBAP) (lub) and radio network subsystem
application part (RNSAP) (lur) protocols as shown in FIGS. 8 and
9.
[0071] FIG. 8 shows signaling of the indication of secondary uplink
carrier activation/deactivation using NBAP. In FIG. 8, the serving
Node B sends an activation/deactivation status report indicating
that the secondary uplink carrier for a particular WTRU has been
activated or deactivated over NBAP (lub) to the RNC, and the RNC
forwards it to non-serving Node-Bs in the active set through NBAP.
FIG. 9 shows signaling of the indication of secondary uplink
carrier activation/deactivation using NBAP and RNSAP. In FIG. 9,
two radio network subsystems (RNSs) are involved. The serving
Node-B sends an activation/deactivation status report indicating
that the secondary uplink carrier for a particular WTRU has been
activated or deactivated over NBAP (lub) to the RNC that controls
the serving Node-B. The RNC then forwards it to non-serving Node-Bs
in the active set that are controlled by the RNC over NBAP. The RNC
also forwards it to other non-serving Node-Bs in the active set
that are controlled by a different RNC over RNSAP (e.g., lur
interface).
[0072] Alternatively, an activation time may be indicated to all
non-serving Node-Bs and, optionally, to the WTRU 110 as well. For
instance, once a deactivation or activation order is sent to the
WTRU 110 the serving Node-B 120 may notify it to other non-serving
Node-Bs. The time at which the WTRU 110 acts to the received order
may be long enough to ensure that all neighboring Node-Bs received
the indication via lub. A certain lub and/or lur latency
requirement may be assumed. Alternatively, the serving Node-B 120
may notify the non-serving Node-Bs first and then sends an order or
other layer 1/layer 2 signaling to the WTRU 110.
[0073] Alternatively, if the secondary DPCCH contains some spare
bits, the WTRU 110 may use one of the spare bits of the secondary
DPCCH to indicate the deactivation of the secondary uplink carrier.
This may ensure that even the cells that are not part of the E-DCH
active set, (i.e., the DCH active set), may receive this
indication.
[0074] Alternatively, if the SI is sent on both uplink carriers and
if the SI in the secondary uplink carrier contains spare bits, the
WTRU 110 may use these spare bits to signal the activation of the
secondary uplink carrier.
[0075] The problem with the usage of unused spare bits or unused
fields in the channels belonging to the secondary uplink carrier is
that these bits or fields may not be used to indicate the
reactivation of the secondary uplink carrier. Therefore, in such
cases the activation of the secondary uplink carrier may be
signaled using other methods described above, which ensure that all
Node-Bs may receive the indication on the anchor carrier.
[0076] The deactivation indication may be sent by the WTRU 110 on
any of the uplink carriers: the primary carrier or the secondary
carrier. Alternatively, the deactivation indication may be
transmitted on the primary uplink carrier or on the uplink carrier
that is being deactivated, (i.e., secondary uplink carrier).
[0077] Similarly, the WTRU 110 may send an indication of
re-activation of the secondary uplink carrier when it is ordered by
the serving Node-B 120 to re-activate transmissions on the
secondary uplink carrier. The re-activation indication may be sent
in a similar manner as the deactivation indication. The
re-activation indication may be sent on the primary carrier.
Alternatively, the serving Node-B may signal to all cells in the
active set that a secondary uplink carrier has been activated. By
way of example, the signaling procedures for indicating that the
secondary carrier has been deactivated may be realized using NBAP
(lub) and RNSAP (lur) RAN protocols as explained above.
[0078] Once a deactivation/activation indication is sent to the
Node-Bs in the E-DCH active set, the WTRU 110 may wait for an
acknowledgment. The current E-DCH operation allows the WTRU 110 to
consider the transmission of a PDU successful as soon as an ACK is
received from any of the cells. In order to ensure that all Node-Bs
in the E-DCH active set received the indication, the WTRU 110 may
wait to receive an ACK from at least one cell in each Radio Link
Set (RLS) (i.e., each Node-B). The WTRU 110 may consider the hybrid
automatic repeat request (HARQ) transmission successful if an ACK
is received from at least one of the cells of each RLS, otherwise a
HARQ retransmission is triggered. If no ACKs are received from at
least one of the RLS and the indication has exceeded the maximum
number of HARQ retransmissions, the WTRU 110 may declare the
transmission of the indication unsuccessful and trigger a new
transmission of the indication. For instance, if the SI is used to
indicate activation/deactivation and according to the criteria
specified above the WTRU 110 fails to successfully transmit this SI
to all Node-Bs, then the SI may be triggered again.
[0079] Alternatively, the WTRU 110 may be configured to repeatedly
send the indication for a pre-configured amount of time. For
instance, the WTRU 110 may send the indication for a determined
number of consecutive TTIs to ensure that all Node-Bs receive the
indication.
[0080] FIG. 10 is a flow diagram showing a method for autonomous
dynamic carrier adjustment in a WTRU 110. The WTRU 110 may be
configured to autonomously or implicitly activate and deactivate
any secondary uplink carrier(s) without an explicit order or signal
from the network. A trigger indicates to the WTRU 110 that a
secondary carrier needs to be activated, deactivated or modified
(1010). The trigger, for example, may be based on inactivity
timers, buffer status, channel conditions, battery usage, or
location based conditions. The WTRU 110 determines the affected
carriers (1020). For example, in the case of dual carriers, the
WTRU 110 may automatically know that it affects only the secondary
carrier. The WTRU 110 then performs procedures for activation,
deactivation, or modification of the determined secondary carriers
(1030). The WTRU 110 notifies the network that a carrier has been
activated or deactivated (1040). The WTRU then adjusts the carriers
and determines a new DTX pattern. Alternatively, the DTX pattern
may be signaled by the network.
[0081] The WTRU 110 may be configured with an inactivity timer or
an inactivity threshold that may be defined in terms of
transmission time intervals (TTIs). The inactivity threshold
defines the time or the number of consecutive TTIs where the WTRU
110 did not have any E-DCH transmissions. When the inactivity of
the E-DCH transmission reaches or exceeds the inactivity threshold
or the inactivity timer expires, the WTRU 110 deactivates the
secondary uplink carrier. The inactivity of the E-DCH transmissions
may refer to no E-DCH transmissions on the secondary uplink carrier
or alternatively may refer to no E-DCH transmissions on any of the
uplink carriers.
[0082] The inactivity timer may be initiated or the inactivity
threshold may be monitored at all times (i.e., even if the WTRU 110
is in continuous transmission mode). Alternatively, the inactivity
timer may be monitored if the WTRU 110 is in WTRU_DTX_cycle_1 or,
alternatively, after the WTRU 110 has moved to WTRU_DTX_cycle_2.
WTRU_DTX_cycle_2 is longer than the WTRU_DTX_cycle_1 and the
WTRU_DTX_cycle_2 is triggered after a configured inactivity period
while in WTRU_DTX_cycle_1. Alternatively, the de-activation of the
secondary uplink carrier may correspond directly to the DTX timing
configured for the primary uplink carrier, (e.g., same timer is
used). In this case, the WTRU 110 deactivates the secondary uplink
carrier when DTX is started on the primary uplink carrier.
Alternatively, the WTRU 110 may deactivate the secondary carrier
when DTX cycle 2 starts on the anchor carrier, (i.e., the
inactivity timer for starting DTX cycle 2 expires).
[0083] Alternatively, the buffer status of the WTRU 110 may act as
an implicit trigger for de-activating or activating the secondary
uplink carrier. The WTRU 110 may be configured with a predetermined
total E-DCH buffer status (TEBS) threshold, which the WTRU 110 may
monitor. If the buffer status of the WTRU 110 is equal to or falls
below the TEBS threshold, the WTRU 110 may de-activate the
secondary uplink carrier. Alternatively, a TEBS threshold combined
with a trigger timer may be used. For example, if the TEBS value is
equal to or below the TEBS threshold for the duration of the
trigger timer, the WTRU 110 may deactivate the secondary uplink
carrier.
[0084] Additionally, the WTRU 110 may use an activation TEBS
threshold to activate the secondary uplink carrier. For example, if
the TEBS value goes above the activation TEBS threshold, optionally
for a pre-configured period of time, the WTRU 110 may re-activate
the secondary uplink carrier. This activation trigger may be
applicable to any of the embodiments disclosed above, regardless of
the method used to deactivate the secondary uplink carrier.
[0085] Alternatively, the WTRU 110 may deactivate the secondary
uplink carrier based on channel conditions and/or power
constraints. For example, as the WTRU 110 moves towards a cell edge
and becomes power limited, the WTRU 110 may autonomously deactivate
the secondary uplink carrier. This may be justified by the fact
that there is little or no gain for the WTRU 110 in utilizing a
larger bandwidth if it is limited by its maximum transmission
power.
[0086] Deactivation of the secondary uplink carrier may be
triggered if the uplink power headroom of one, both, any, or a
combination of the uplink carriers goes below a certain threshold,
optionally for a configured amount of time. Alternatively,
deactivation of the secondary uplink carrier may be triggered if
the received power of the common pilot channel (CPICH) from the
primary downlink carrier falls below a certain threshold. The
received power of the CPICH from any downlink carrier may be used.
Alternatively, deactivation of the secondary uplink carrier may
also be triggered if the WTRU 110 receives a predetermined number
of successive increase (i.e. UP) power control commands from the
serving Node-B 120 on one, both, or any of the carriers.
Alternatively, deactivation of the secondary uplink carrier may be
triggered if the WTRU 110 has enough data and grant to fully
utilize the power headroom on the anchor carrier (i.e., the WTRU
110 is limited by its maximum transmission power). Alternatively,
deactivation of the secondary uplink carrier maybe triggered if the
power headroom on the secondary uplink carrier is smaller than the
power headroom on the anchor uplink carrier. Alternatively,
deactivation of the secondary uplink carrier may be triggered if
the WTRU 110 has not been able to transmit any data on the
secondary uplink carrier for a pre-configured amount of time, due
to power limitations in the secondary uplink carrier. It should be
noted that the thresholds described above may be predefined or
configured by a higher layer, such as radio resource control (RRC)
layer.
[0087] Upon autonomously deactivating the secondary uplink carrier,
the WTRU 110 may send an indication to the network to signal the
deactivation of the secondary uplink carrier. This may be performed
using one or a combination of the following methods or additionally
using one or a combination of the methods for deactivation
indication described above. A special value of the SI may be used
to indicate that the WTRU 110 has deactivated, or is going to
deactivate, the secondary uplink carrier. For instance, the value
of TEBS set to zero may be used to report implicit deactivation of
the secondary uplink carrier. Alternatively, the WTRU 110 may use
power headroom of zero to indicate implicit deactivation of the
secondary uplink carrier. If two power headroom fields are present
in the SI field, the WTRU 110 may report power headroom of zero for
the secondary uplink carrier. Alternatively, the TEBS value lower
than a configured threshold may be used as an indication.
[0088] Alternatively, layer 2 signaling in the MAC-i header using
the special value of the LCH-ID field and using, for example, one
or two values of the 4 spare bits may be used to indicate the
deactivation of the secondary uplink carrier. Alternatively, a
special or reserved value of the E-TFCI may be transmitted on the
E-DPCCH. The WTRU 110 may send the special E-TFCI when there is no
data to transmit on the corresponding uplink carrier (i.e., E-DPDCH
is not transmitted).
[0089] The de-activation indication may be sent by the WTRU 110 on
any of the uplink carriers: the primary carrier or the secondary
carrier. Alternatively, the de-activation indication may be
transmitted on the primary carrier or on the carrier that is being
deactivated (i.e., secondary uplink carrier).
[0090] Alternatively, the WTRU 110 may deactivate the secondary
uplink carrier without indicating it to the network.
[0091] For all the embodiments disclosed above the WTRU 110 may
deactivate the secondary uplink carrier a determined number of
slots or a determined number of TTIs after receptions of the
explicit indication or after the triggering of the implicit
criteria. The time for activation or deactivation may take into
account the time to send an acknowledgment or indication to the
network and optionally the time for all Node-Bs to be notified via
lub signaling.
[0092] For the implicit triggering, where the WTRU 110 sends an
indication to the network, the WTRU 110 may wait until an ACK is
received for the given message prior to deactivating the secondary
uplink carrier. Optionally, the WTRU 110 may wait a determined
number of slots or a determined number of TTIs prior to activating
or deactivating the secondary uplink carrier after an ACK is
received. The deactivation may be acknowledged as described above.
For instance, the WTRU 110 may wait to receive an ACK from at least
one cell from each RLS.
[0093] The uplink and downlink secondary carriers may be activated
and de-activated in coordination. In accordance with one
embodiment, the secondary uplink carrier may be activated upon
activation of the secondary downlink carrier according to any
trigger for activating the secondary downlink carrier (e.g.,
HS-SCCH order). This activation may take place even if no data
needs to be transmitted on the uplink, as the purpose may be to
provide HS-DPCCH feedback for the secondary downlink carrier. The
activation may take place a certain number of sub-frames after
activation of the secondary downlink carrier.
[0094] In accordance with another embodiment, the secondary uplink
carrier may be de-activated upon de-activation of the secondary
downlink carrier according to any trigger for de-activating the
secondary downlink carrier, (e.g., HS-SCCH order). The
de-activation of the secondary uplink carrier may require as an
additional condition that no data transmission is on-going in the
uplink direction (i.e., E-DCH) on the secondary uplink carrier,
and/or that the WTRU 110 buffer is empty.
[0095] In accordance with another embodiment, the secondary
downlink carrier may be activated upon activation of the secondary
uplink carrier according to any previously defined trigger for
activating the secondary uplink carrier, (e.g., HS-SCCH order).
This activation may take place even if no data needs to be
transmitted on the downlink, as the purpose may be to provide
downlink control channels for the secondary uplink carrier. The
activation may take place a certain number of sub-frames after
activation of the secondary uplink carrier.
[0096] In accordance with another embodiment, the secondary
downlink carrier may be de-activated upon de-activation of the
secondary uplink carrier according to any trigger for de-activating
the secondary uplink carrier, (e.g., HS-SCCH order). The
de-activation of the secondary downlink carrier may require as an
additional condition that no data transmission is on-going in the
downlink direction (i.e., HS-DSCH) on the secondary downlink
carrier.
[0097] In accordance with another embodiment, both uplink and
downlink carriers may be both activated or de-activated by a single
trigger. The trigger may be the reception of an HS-SCCH order
indicating the activation or de-activation of both carriers. This
may be achieved, for instance, by defining a new HS-SCCH order
type. Alternatively, the trigger may be the reception of an E-AGCH
signal indicating the activation or de-activation of both carriers.
Such E-AGCH signal may, for example, comprise the combination of
bits corresponding to "INACTIVE", or combination corresponding to
"zero grant" with the scope bit set to "all HARQ processes." A
distinct E-RNTI value may be used to indicate that the signal is
intended to activate or de-activate both the uplink and downlink
carriers. For the de-activation of both carriers, the trigger may
be that the uplink buffer status of the WTRU 110 has been lower
than a threshold (or zero) for a pre-determined amount of time, and
no data has been received on the secondary carrier for a
pre-determined amount of time. For the activation of both carriers,
the trigger may be that the uplink buffer status of the WTRU 110
has been higher than a threshold (or zero) for a pre-determined
amount of time, or an amount of data higher than a pre-determined
threshold has been received on the anchor downlink carrier within a
pre-determined amount of time.
[0098] FIG. 11 is a flow diagram illustrating procedures associated
with deactivating a secondary uplink carrier. The methods may be
applied to all secondary uplink carriers. Alternatively, each
secondary uplink carrier may have a separate procedure that is
determined by the WTRU 110 or signaled by the network. Upon
receiving a signal or a trigger, the WTRU 110 selects which uplink
carrier(s) to deactivate. Transmissions on the selected carrier(s)
are terminated (1110). The transmissions may be terminated
immediately, after a predetermined time period, or after the
conclusion of any transmissions scheduled prior to the deactivation
signal (1120). The WTRU 110 then stops monitoring any associated
control channels (1130). The WTRU 110 may stop transmission of any
associated control channels (1140). The WTRU 110 may further
deactivate selected downlink carriers, which may be determined
based on explicit signaling, implicit signaling or autonomously
(1150). Once the secondary carrier(s) are deactivated, the WTRU 110
may reconfigure the DTX pattern (1160).
[0099] When deactivating the secondary uplink carrier using one of
the embodiments described above or any other methods, the WTRU 110
may stop transmitting the secondary uplink DPCCH or any uplink
control signal used for the secondary uplink carrier, and/or may
stop monitoring and stop reception of the E-HICH, E-RGCH, and
E-AGCH associated to the secondary uplink carrier, if applicable.
In addition, the WTRU 110 may flush the HARQ entity associated to
the supplementary carrier. If the WTRU 110 is configured to send on
an HS-DPCCH on each uplink carrier for downlink operation, the WTRU
110 may stop transmission of HS-DPCCH on the secondary uplink
carrier. If DC-HSDPA is still activated, the WTRU 110 may start
transmitting HS-DPCCH for the secondary downlink carrier on the
primary uplink carrier using a separate HS-DPCCH code or
alternatively on one code for each carrier using 3GPP Release 8
HS-DPCCH code formatting. Optionally, the WTRU 110 may also
autonomously deactivate the secondary downlink carrier as well when
the secondary uplink carrier is deactivated.
[0100] In addition, the following actions may occur when the
de-activation occurs through RRC signaling. The WTRU 110 may stop
E-DCH transmission and reception procedures on the supplementary
carrier, flush the HARQ entity associated to the supplementary
carrier, release the HARQ processes of the HARQ entity associated
to the supplementary carrier, and/or clear E-RNTI value(s)
associated to the secondary carrier.
[0101] FIG. 12 is a flow diagram illustrating procedures associated
with activating a secondary uplink carrier. The WTRU 110 determines
any uplink carrier(s) to activate (1210). The WTRU 110 determines
an initial transmit power for an associated control channel (1220).
The WTRU 110 determines an initial uplink transmit power for the
uplink data channel (1230). The WTRU 110 then sets the DTX pattern
(1240).
[0102] When the secondary uplink carrier is activated or initially
configured, the WTRU 110 may start DPCCH transmissions a determined
number of slots or a determined number of TTIs prior to initiating
E-DCH transmissions on the secondary uplink carrier. The determined
number of slots or TTIs may be configured by a higher layer. This
may allow the WTRU 110 to establish the right power control loop in
the secondary uplink carrier and start transmission at the right
power level. In addition, a post-verification period may be defined
to allow the WTRU 110 to start E-DCH transmission before
synchronization is confirmed. The duration of the post-verification
period may be smaller or larger than the post-verification period
used for instance in the conventional synchronization procedures A,
AA or B. A fast activation procedure may be defined for the
secondary uplink carrier. Such fast activation relies on the fact
that the WTRU 110 may use the information from the transmission
power of the primary DPCCH carrier when establishing the
transmission power on the secondary DPCCH carrier, as described
below.
[0103] Embodiments for setting the initial DPCCH transmission power
upon activation of the secondary uplink carrier are disclosed
hereafter.
[0104] The initial DPCCH transmission power on the secondary uplink
carrier may be set to the same value as the DPCCH transmission
power on the primary uplink carrier, a predetermined number (n) of
slots prior to the activation time (n.gtoreq.0).
[0105] Alternatively, the initial DPCCH transmission power on the
secondary uplink carrier may be set to the same value as the DPCCH
transmission power on the primary uplink carrier, a predetermined
number (n) of slots prior to the activation time (n.gtoreq.0), plus
or minus an offset (in dB). The offset may be a fixed
pre-determined value. Alternatively, the offset may be a value
signaled by the network at physical layer, MAC layer or RRC layer.
The offset may be broadcast on system information. The network may
determine the offset value based (in part) on the relative uplink
interference conditions between the primary and supplementary
uplink carriers. For instance, the offset may be a fixed value plus
the difference between the interference level at the supplementary
uplink carrier and the interference level at the primary uplink
carrier. Alternatively, the offset value may be derived by the WTRU
110 based on uplink interference values signaled by the network.
The network may signal the interference on each of the uplink
carriers on system information block 7 (SIB7) via the corresponding
downlink carriers. Alternatively, the network may also signal the
interference on both uplink carriers on the system information
block via the primary carrier (or the supplementary carrier) in
order to accelerate acquisition of the values. The network may also
signal the interference on both uplink carriers using dedicated
signaling (PHY, MAC or RRC) along with an activation command or
subsequent to an implicit activation by the WTRU 110.
Alternatively, the offset may be determined based on the difference
between the DPCCH power levels of the primary and supplementary
uplink carriers observed the last time when both uplink carriers
were activated. The value may be averaged over a certain time
interval. Alternatively, the offset may be determined as per any
one of the methods above, or any other method, and the choice of
the method may depend on the amount of time elapsed since the
supplementary uplink carrier was last activated. The WTRU 110 runs
a timer(s) upon de-activation of the supplementary uplink
carrier(s), and upon expiration of the timer(s) a corresponding
method to determine the offset is selected.
[0106] The initial DPCCH transmission power on the secondary uplink
carrier may be set to a fixed value signaled by the network at PHY,
MAC or RRC layers along with an activation command or subsequent to
an implicit activation by the WTRU 110. The initial DPCCH power may
be broadcast on system information. The network may determine the
initial DPCCH power based (in part) on the relative uplink
interference conditions between the primary and supplementary
uplink carriers.
[0107] The initial DPCCH transmission power on the secondary uplink
carrier may be set to the same value signaled via RRC signaling for
initial DPCCH power in the primary uplink carrier.
[0108] At the network side, the initial DPDCH or F-DPCH
transmission power upon activation of the secondary uplink carrier
may be determined according to one or a combination of the
following. The initial F-DPCH transmission power on the secondary
downlink carrier may be set to the same value as the F-DPCH
transmission power on the primary downlink carrier, a predetermined
number (n) of slots prior to the activation time (n.gtoreq.0).
[0109] The initial F-DPCH transmission power on the secondary
downlink carrier may be set to the same value as the F-DPCH
transmission power on the primary downlink carrier, a predetermined
number (n) of slots prior to the activation time (n.gtoreq.0), plus
an offset (in dB). The offset may be a fixed pre-determined value.
Alternatively, the offset may be a value signaled by the WTRU 110
at PHY, MAC (e.g., modified scheduling information) or RRC (e.g.,
measurement report) on the primary uplink carrier subsequent to
explicit or implicit activation of the secondary uplink carrier.
The WTRU 110 may determine the offset value based on measured
common pilot channel (CPICH) Ec/No, CPICH received signal code
power (RSCP), channel quality indicator (CQI) on both downlink
carriers. Alternatively, the offset may be determined by the
network based on a measurement report or other information sent by
the WTRU 110. The WTRU 110 may trigger the transmission of the
measurement report upon implicit activation of the secondary uplink
carrier or upon receiving an explicit activation command from the
network. The WTRU 110 may trigger the transmission of CQI
information for both downlink carriers (the primary and secondary
downlink carriers corresponding to the uplink carrier to activate)
over the HS-DPCCH of the primary uplink carrier upon implicit or
explicit activation of the secondary uplink carrier.
[0110] When the secondary uplink carrier is activated, the WTRU 110
may use a default grant value for the initial E-DCH transmission,
which is a value signaled to the WTRU 110 for use when the
secondary uplink carrier is activated. The default grant value may
be signaled to the WTRU 110 through RRC signaling upon
configuration of the secondary uplink carrier. Alternatively, the
WTRU 110 may use the same serving grant as being used in the
primary uplink carrier at the time of the activation of the
secondary uplink carrier. Alternatively, the WTRU 110 may trigger
scheduling information and wait for an absolute grant for the
secondary uplink carrier. In this case, the activation of the
secondary uplink carrier may trigger the WTRU 110 to send
scheduling information.
[0111] Upon activation of the secondary uplink carrier, the WTRU
110 may use the same DTX status as the primary uplink carrier. When
the secondary uplink carrier is activated, the WTRU 110 may start
using the same DTX and/or DRX pattern as in the primary uplink
carrier. Alternatively, the WTRU 110 may start in a continuous mode
in the secondary uplink carrier, or alternatively may start in
WTRU_DTX_cycle_1 or WTRU_DTX_cycle_2.
[0112] Embodiments for controlling DTX/DRX patterns to optimize the
battery saving and increased capacity with dual uplink carrier
operation are disclosed hereafter. A single carrier WTRU 110 has
two level DTX patterns: the physical layer DTX with two DTX cycles
(WTRU_DTX_cycle_1 and WTRU_DTX_cycle_2) and the MAC layer DTX which
is controlled by the parameter MAC_DTX_cycle.
[0113] In accordance with one embodiment, the WTRU 110 uplink DPCCH
transmission pattern and bursts on the secondary uplink carrier may
be aligned with the uplink DPCCH transmission pattern and bursts on
the primary uplink carrier. For example, the network signals one
set of DTX/DRX parameters that may be applied to all uplink
carriers. The MAC_DTX_cycle may be applicable to all uplink
carriers and E-TFC selection may be performed on all uplink
carriers at the same time.
[0114] Due to the fact that the WTRU 110 has two physical layer DTX
cycles (WTRU_DTX_cycle_1 and WTRU_DTX_cycle_2) and the
WTRU_DTX_cycle_2 is triggered after a configured inactivity period
while in WTRU_DTX_cycle_1, a method to process the aligned DTX
pattern may be defined. For example, the inactivity period may be
applied to both uplink carriers and the definition of the
inactivity threshold for WTRU_DTX_cycle_2 may be defined as the
number of consecutive E-DCH TTIs without an E-DCH transmission on
all uplink carriers, and if there is no E-DCH transmission on both
uplink carriers for the inactivity threshold, the WTRU 110 may
immediately move from WTRU_DTX_cycle_1 to WTRU_DTX_cycle_2 on any
of the uplink carriers. Alternatively, the WTRU 110 may keep track
of E-DCH transmission on each uplink carrier individually, and if
one of the uplink carriers does not have an E-DCH transmission for
inactivity threshold, the WTRU 110 may move both uplink carriers to
WTRU_DTX_cycle_2. Alternatively, if the secondary uplink carrier
has been inactive for the configured amount of time, the secondary
uplink carrier may move to the WTRU_DTX_cycle_2. The uplink DPCCH
burst patterns may be the same on the uplink carriers.
[0115] The activation of DTX/DRX may be signaled via an HS-SCCH
order over any of the downlink carriers and be applicable to both
uplink carriers. This is applicable to the case where the WTRU 110
has the same DTX/DRX status on both uplink carriers. Alternatively,
the HS-SCCH order may be used to control the DTX/DRX status on the
uplink carriers independently. For instance, the downlink and
uplink carriers are paired, and any order on a downlink carrier may
be applicable to the corresponding uplink carrier.
[0116] In accordance with another embodiment, the WTRU 110 may use
the DTX patterns with identical periods on both uplink carriers
with different offsets so that the patterns are staggered, (i.e.,
the DPCCH transmissions on each uplink carrier do not take place at
the same time). This configuration may be combined with another
embodiment where the WTRU 110 applies E-DCH start time
restrictions, (i.e., MAC DTX), on a per-carrier basis. This means
that the WTRU 110 does not perform E-DCH transmission (or E-TFC
selection) in every sub-frame for a given uplink carrier. The sets
of sub-frames, (i.e., patterns), where E-DCH transmission is
allowed may be different, (e.g., staggered), between the uplink
carriers. The WTRU 110 may use per-carrier E-DCH start time
restriction patterns that coincide with the corresponding
per-carrier DTX patterns to minimize or eliminate the occurrences
of having simultaneous E-DCH transmission on both carriers.
[0117] In accordance with another embodiment, the WTRU 110 may use
independent DTX cycles for the primary and secondary uplink
carriers. For example, the physical layer DTX cycles
(WTRU_DTX_cycle_1 and WTRU_DTX_cycle_2) may have different values
for both uplink carriers. For the purpose of this embodiment,
WTRU_P_DTX_cycle_x and WTRU_S_DTX_cycle_x are referred to as the
DTX cycles applicable to the primary and secondary uplink carriers,
respectively, where x refers to cycle 1 or 2.
[0118] The network may independently signal WTRU_P_DTX_cycle_1 or
WTRU_P_DTX_cycle_2, or WTRU_S_DTX_cycle_1 or WTRU_S_DTX_cycle_2.
The values WTRU_S_DTX_cycle_x may be an integer multiple or
divisors of the value WTRU_P_DTX_cycle_x. The network may signal
one set of DTX cycles for the primary uplink carrier and the WTRU
110 determines the cycle to be used for the secondary uplink
carrier based on the factor, N, which may be predefined or signaled
by a higher layer. For example:
WTRU_S_DTX_cycle_x=WTRU_P_DTX_Cycle_x.times.N Equation (1)
[0119] Alternatively, one DTX_cycle may be configured for the
secondary uplink carrier. For example, the primary uplink carrier
may be configured with both DTX cycles 1 and 2, but the secondary
uplink carrier may be configured with one DTX cycle
(WTRU_S_DTX_cycle).
[0120] The WTRU 110 may move from continuous reception to
WTRU_DTX_cycle_1 in the primary carrier and to WTRU_S_DTX_cycle in
the secondary carrier. WTRU_S_DTX_cycle may be equivalent to
WTRU_DTX_cycle_1, WTRU_DTX_cycle_2, or a different network
configured value.
[0121] After no E-DCH transmission for an inactivity threshold, the
primary uplink carrier may move to DTX cycle 2, and the
supplementary carrier may be optionally deactivated instead of
moving to DTX cycle 2. Since the WTRU 110 is considered to be in
low E-DCH activity, the WTRU 110 may deactivate the secondary
uplink carrier.
[0122] The MAC DTX cycle and pattern may be the same for both
uplink carriers. This may allow the WTRU 110 to schedule on any of
the uplink carriers if E-DCH data is present, possibly optimizing
on grant, power, etc. Alternatively, the MAC DTX cycle may be
similar on both uplink carriers, but the patterns between both
uplink carriers may be offset by a configured offset value.
Alternatively, the MAC DTX cycle may be different values for each
uplink carrier.
[0123] The same may be applicable to WTRU 110 physical layer DTX
cycle. The WTRU 110 DTX pattern of the secondary uplink carrier may
be offset by a predetermined or configured offset value from the
WTRU 110 DTX pattern of the primary uplink carrier.
[0124] Alternatively, the WTRU 110 may have the same DTX cycle and
offset configuration depending on the activity of each uplink
carrier. The WTRU 110 may be allowed to be operating in continuous
reception in one uplink carrier and in DTX cycle 1 or 2 on the
other uplink carrier. Alternatively, the anchor uplink carrier may
be operating with DTX cycle 1 and the secondary uplink carrier with
DTX cycle 2. This may allow the WTRU 110 to save on transmitting
DPCCH and other control channels on one of the uplink carriers if
no data may be transmitted.
[0125] With single uplink carrier activation, if the WTRU 110 has
DTX activated and E-DCH scheduled data is transmitted, the WTRU 110
may monitor the E-AGCH and E-RGCH from all cells in the active set
for "Inactivity Threshold for WTRU 110 Grant Monitoring" TTIs. With
multi carrier or dual cell operation, the WTRU 110 may monitor the
E-AGCH and E-RGCH associated to both uplink carriers if any E-DCH
transmission is triggered (independent of the uplink carrier being
used) for "Inactivity Threshold for WTRU 110 Grant Monitoring"
TTIs. Alternatively, the WTRU 110 may monitor the E-AGCH and E-RGCH
associated to the uplink carrier for which E-DCH transmission was
present.
[0126] Although features and elements are described above in
particular combinations, each feature or element can be used alone
without the other features and elements or in various combinations
with or without other features and elements. The methods or flow
charts provided herein may be implemented in a computer program,
software, or firmware incorporated in a computer-readable storage
medium for execution by a general purpose computer or a processor.
Examples of computer-readable storage mediums include a read only
memory (ROM), a random access memory (RAM), a register, cache
memory, semiconductor memory devices, magnetic media such as
internal hard disks and removable disks, magneto-optical media, and
optical media such as CD-ROM disks, and digital versatile disks
(DVDs).
[0127] Suitable processors include, by way of example, a general
purpose processor, a special purpose processor, a conventional
processor, a digital signal processor (DSP), a plurality of
microprocessors, one or more microprocessors in association with a
DSP core, a controller, a microcontroller, Application Specific
Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs)
circuits, any other type of integrated circuit (IC), and/or a state
machine.
[0128] A processor in association with software may be used to
implement a radio frequency transceiver for use in a wireless
transmit receive unit (WTRU), user equipment (UE), terminal, base
station, radio network controller (RNC), or any host computer. The
WTRU may be used in conjunction with modules, implemented in
hardware and/or software, such as a camera, a video camera module,
a videophone, a speakerphone, a vibration device, a speaker, a
microphone, a television transceiver, a hands free headset, a
keyboard, a Bluetooth.RTM. module, a frequency modulated (FM) radio
unit, a liquid crystal display (LCD) display unit, an organic
light-emitting diode (OLED) display unit, a digital music player, a
media player, a video game player module, an Internet browser,
and/or any wireless local area network (WLAN) or Ultra Wide Band
(UWB) module.
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