U.S. patent application number 16/247171 was filed with the patent office on 2019-05-16 for csi-rs sequence generation and mapping and dmrs scrambling id configuration.
This patent application is currently assigned to Intel IP Corporation. The applicant listed for this patent is Intel IP Corporation. Invention is credited to Alexei Davydov, Sameer Pawar, Avik Sengupta.
Application Number | 20190149294 16/247171 |
Document ID | / |
Family ID | 66433746 |
Filed Date | 2019-05-16 |
United States Patent
Application |
20190149294 |
Kind Code |
A1 |
Pawar; Sameer ; et
al. |
May 16, 2019 |
CSI-RS SEQUENCE GENERATION AND MAPPING AND DMRS SCRAMBLING ID
CONFIGURATION
Abstract
In some embodiments, an apparatus of a Fifth Generation (5G)
NodeB (gNB) comprises one or more baseband processors to encode one
or more channel state information reference signals (CSI-RS) to be
transmitted to a user equipment (UE). The one or more CSI-RS
signals comprise a complex sequence mapped to a resource element
(RE) such that all CSI-RS ports use an identical sequence for the
one or more CSI-RS signals in a symbol. In other embodiments, the
gNB comprises one or more baseband processors to encode a
scrambling identity (ID) configuration for one or more demodulation
reference signals (DMRS), wherein the scrambling ID configuration
indicates one of two scrambling IDs to be signaled to a UE.
Inventors: |
Pawar; Sameer; (Santa Clara,
CA) ; Sengupta; Avik; (San Jose, CA) ;
Davydov; Alexei; (Nizhny Novgorod, RU) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Intel IP Corporation |
Santa Clara |
CA |
US |
|
|
Assignee: |
Intel IP Corporation
Santa Clara
CA
|
Family ID: |
66433746 |
Appl. No.: |
16/247171 |
Filed: |
January 14, 2019 |
Current U.S.
Class: |
370/329 |
Current CPC
Class: |
H04L 5/0007 20130101;
H04W 88/02 20130101; H04W 72/1263 20130101; H04L 5/0094 20130101;
H04L 25/0226 20130101; H04L 5/0048 20130101; H04L 27/20 20130101;
H04L 27/2613 20130101; H04B 7/02 20130101 |
International
Class: |
H04L 5/00 20060101
H04L005/00; H04L 27/20 20060101 H04L027/20; H04W 72/12 20060101
H04W072/12 |
Claims
1. An apparatus of a Fifth Generation (5G) NodeB (gNB), comprising:
one or more baseband processors to encode one or more channel state
information reference signals (CSI-RS) to be transmitted to a user
equipment (UE), wherein the one or more CSI-RS signals comprise a
complex sequence mapped to a resource element (RE) such that all
CSI-RS ports use an identical sequence for the one or more CSI-RS
signals in a symbol; and a memory to store the one or more CSI-RS
signals.
2. The apparatus of claim 1, wherein different resource elements
occupied by a CSR-RS port have different complex values for the
complex sequence.
3. The apparatus of claim 1, wherein the complex sequence comprises
a Gold sequence quadrature phase shift keying (QPSK) sequence.
4. The apparatus of claim 1, further comprising a transceiver to
transmit the one or more CSI-RS signals to the UE and to receive a
channel state information (CSI) report from the UE in response to
the one or more CSI-RS signals.
5. An apparatus of a user equipment (UE), comprising: one or more
baseband processors to decode one or more channel state information
reference signals (CSI-RS) received from a Fifth Generation (5G)
NodeB (gNB), wherein the one or more CSI-RS signals comprise a
complex sequence mapped to a resource element (RE) such that all
CSI-RS ports use an identical sequence for the one or more CSI-RS
signals in a symbol; and a memory to store the one or more CSI-RS
signals.
6. The apparatus of claim 5, wherein different resource elements
occupied by a CSR-RS port have different complex values for the
complex sequence.
7. The apparatus of claim 5, wherein the complex sequence comprises
a Gold sequence quadrature phase shift keying (QPSK) sequence.
8. The apparatus of claim 5, further comprising a transceiver to
receive the one or more CSI-RS signals from the gNB, and to
transmit a channel state information (CSI) report to the gNB in
response to the one or more CSI-RS signals.
9. One or more non-transitory storage media having instructions
stored thereon that, when executed by an apparatus of a Fifth
Generation (5G) NodeB (gNB), result in: encoding one or more
channel state information reference signals (CSI-RS) to be
transmitted to a user equipment (UE), wherein the one or more
CSI-RS signals comprises a complex sequence mapped to a resource
element (RE) such that all CSI-RS ports use an identical sequence
for the CSI-RS in symbol; and processing a channel state
information (CSI) report received from the UE in response to the
one or more CSI-RS signals
10. The one or more non-transitory storage media of claim 9,
wherein different resource elements occupied by a CSR-RS port have
different complex values for the complex sequence.
11. The one or more non-transitory storage media of claim 9,
wherein the complex sequence comprises a Gold sequence quadrature
phase shift keying (QPSK) sequence.
12. An apparatus of a Fifth Generation (5G) NodeB (gNB),
comprising: one or more baseband processors to encode a scrambling
identity (ID) configuration for one or more demodulation reference
signals (DMRS), wherein the scrambling ID configuration indicates
one of two scrambling IDs to be signaled to a user equipment (UE);
and a memory to store the scrambling ID configuration.
13. The apparatus of claim 12, wherein the scrambling ID
configuration is to be signaled as part of a channel state
information reference signal (CSI-RS) configuration.
14. The apparatus of claim 12, wherein the signaling is performed
as a part of a synchronization signal block (SSB)
configuration.
15. The apparatus of claim 12, wherein the scrambling ID
configuration indicates one of two 16-bit scrambling IDs
16. The apparatus of claim 12, wherein the scrambling ID
configuration comprises a value indicated by a transmission
configuration indication (TCI) state in downlink control
information (DCI) when parameter TCI-PresentInDCI is enabled,
wherein the TCI state is signaled in the DCI associated with
ControlResourceSet (CORESET) scheduling a physical downlink shared
channel (PDSCH) or a physical uplink shared channel (PUSCH).
17. The apparatus of claim 17, wherein the scrambling ID
configuration comprises a value of 0 when parameter
TCI-PresentInDCI is disabled.
18. One or more non-transitory storage media having instructions
stored thereon that, when executed by an apparatus of a Fifth
Generation (5G) NodeB (gNB), result in: encoding a scrambling
identity (ID) configuration for one or more demodulation reference
signals (DMRS), wherein the scrambling ID configuration indicates
one of two scrambling IDs to be signaled to a user equipment (UE)
using 1-bit in downlink control information (DCI) associated with
ControlResourceSet (CORESET) scheduling a physical downlink shared
channel (PDSCH) or a physical uplink shared channel (PUSCH); and
transmitting the scrambling ID configuration to the UE.
19. The one or more non-transitory storage media of claim 18,
wherein the scrambling ID configuration is to be signaled as part
of a channel state information reference signal (CSI-RS)
configuration.
20. The one or more non-transitory storage media of claim 18,
wherein the signaling is performed as a part of a synchronization
signal block (SSB) configuration.
Description
BACKGROUND
[0001] In radio systems, a multiple-input, multiple-output (MIMO)
system relies on a plurality of transmit (Tx) antennas and receive
(Rx) antennas to provide spatial diversity, multiplexing, and array
gains in the downlink and uplink channels. In the downlink, the
transmitter can increase the performance by using channel state
information (CSI) about the downlink channel observed by the
receiver. The CSI can be obtained by the transmitter from the
receiver from an estimation of the uplink channel and by using
channel reciprocity of the wireless channel, or from quantized
feedback measured by the receiver.
[0002] A channel state information reference signal (CSI-RS) is a
reference signal that supports many functionalities in NR including
channel measurement for CSI calculation. A demodulation reference
signal (DMRS) is a user specific reference signal which can be used
for channel estimation for physical downlink shared channel (PDSCH)
and physical uplink shared channel (PUSCH) data demodulation. In
Release 15 of the New Radio (NR) standard, a DMRS is generated
using a length 31 Gold Sequence similar to the Long Term Evolution
(LTE) standard. The initialization for the Gold sequence involves
the configuration of a 16-bit user specific scrambling identifier
ID in order to randomize interference and reduce cross-correlation
between different DMRS sequences. In the NR standard, two such
scrambling IDs can be configured per user.
DESCRIPTION OF THE DRAWING FIGURES
[0003] Claimed subject matter is particularly pointed out and
distinctly claimed in the concluding portion of the specification.
However, such subject matter may be understood by reference to the
following detailed description when read with the accompanying
drawings in which:
[0004] FIG. 1 is a diagram of a Fifth Generation (5G) New Radio
(NR) access network in which channel state information reference
signals (CSI-RS) may be utilized in accordance with one or more
embodiments;
[0005] FIG. 2 is a diagram of process of scrambling ID
configuration for demodulation reference signals (DMRS) in
accordance with one or more embodiments.
[0006] FIG. 3 illustrates an architecture of a system of a network
in accordance with some embodiments.
[0007] FIG. 4 illustrates example components of a device in
accordance with some embodiments.
[0008] FIG. 5 illustrates example interfaces of baseband circuitry
in accordance with some embodiments.
[0009] It will be appreciated that for simplicity and/or clarity of
illustration, elements illustrated in the figures have not
necessarily been drawn to scale. For example, the dimensions of
some of the elements may be exaggerated relative to other elements
for clarity. Further, if considered appropriate, reference numerals
have been repeated among the figures to indicate corresponding
and/or analogous elements.
DETAILED DESCRIPTION
[0010] In the following detailed description, numerous specific
details are set forth to provide a thorough understanding of
claimed subject matter. It will, however, be understood by those
skilled in the art that claimed subject matter may be practiced
without these specific details. In other instances, well-known
methods, procedures, components and/or circuits have not been
described in detail.
[0011] Referring now to FIG. 1, a diagram of a Fifth Generation
(5G) New Radio (NR) access network in which channel state
information reference signals (CSI-RS) may be utilized in
accordance with one or more embodiments will be discussed. As shown
in FIG. 1, a Fifth Generation (5G) New Radio (NR) access network
100 may include a 5G NodeB (gNB) 112 to communicate with one or
more user equipment (UE) devices 110 to receive messages and/or
data in the downlink 114, and to send messages and/or data to gNB
112 in the uplink 116. In one or more embodiments, UE 110 may
receive measurement configuration information such as MeasObjectNR
from gNB 112 as a radio resource control (RRC) message in the
downlink 114 to configure the UE 110 to perform Reference Signal
Received Power (RSRP) or Reference Signal Received Quality (RSRQ)
measurements on a neighbor or target cell (not shown) for example
via channel state information reference signals (CSI-RS)
transmitted by the neighbor or target cell 114. RSRP is the average
power of resource elements (RE) that carrier cell specific
Reference Signals (RS) over the entire bandwidth. RSRP is measured
in the symbols that carry the cell specific Reference Signals (RS).
The UE 110 measures the power of multiple resource elements (REs)
that carry the Reference Signals (RS), and then averages the power
over the measured REs.
[0012] In accordance with one or more embodiments, CSI-RS sequence
generation and its mapping to the physical resource elements for NR
is provided. The design utilized by access network 100 supports
potentially more than one complex symbol per physical resource
block orthogonal frequency-division multiplexing (OFDM) symbol
while using the same sequence for all the CSI-RS ports in a symbol.
The CSI-RS resources are described in New Radio Release 15 of the
Third Generation Partnership Project (3GPP) in 3GPP Technical
Specification (TS) 38.211V1.3.0 (2017-12) as follows.
1. CSI-RS-Resource
[0013] An X={1, 2, 4, 8, 12, 16, 24, 32} port CSI-RS resource is
constructed from a combination of one or more CSI-RS components. A
CSI-RS resource component in a PRB consists of adjacent Y resource
elements in frequency and Z adjacent resource elements in time
domain. The possible pairs of values of (Y, Z)={(2, 1), (4, 1), (2,
2)}. The possible combinations of CSI-RS resource components to
make up an X port CSI-RS resource are described in Table 1. The
time-domain locations l.sub.0 and l.sub.1 are defined relative to
the starting positions of a CSI-RS resource within a slot
l.di-elect cons.{0, 1, . . . , 13} as configured by the
higher-layer parameter. The frequency-domain location k.sub.i of
the CSI-RS resource component is given by a bitmap provided by the
higher-layer parameter. The values k.sub.i in Table 1 corresponds
to the i.sup.th set bit in the bitmap, starting from b.sub.0, with
the bitmap and value of k.sub.i given by
[b.sub.3 . . . b.sub.0], k.sub.i=f(i) for row 1 of Table 1
[b.sub.11 . . . b.sub.0], k.sub.i=f(i) for row 2 of Table 1
[b.sub.2 . . . b.sub.0], k.sub.i=4f(i) for row 4 of Table 1
[b.sub.5 . . . b.sub.0], k.sub.i=2f(i) for all other cases where
f(i) is the bit number of the i.sup.th set bit in the bitmap.
2. Sequence Generation
[0014] The UE shall assume the reference-signal sequence r(m) is
defined by
r ( m ) = 1 2 ( 1 - 2 c ( 2 m ) ) + j 1 2 ( 1 - 2 c ( 2 m + 1 ) ) .
##EQU00001##
where the pseudo-random sequence c(i) is defined in clause 5.2.1
[1]. The pseudo-random sequence generator shall be initialized
with
c.sub.init=(2.sup.10(14n.sub.s,f+l+1)(2n.sub.ID+1)+n.sub.ID)mod
2.sup.31
at the start of each OFDM symbol where n.sub.s,f is the slot number
within a radio frame, l is the OFDM symbol number within a slot,
and n.sub.ID equals the higher-layer parameter ScramblingID.
[0015] In addition to the above CSI-RS details reviewed from the NR
Rel-15, we have agreement from 3GPP RAN1 meeting #91 [2] that
CSI-RS sequence, for one OFDM symbol, is same for all the ports and
supports more than one complex symbol per PRB per symbol.
Considering these constraints, we propose a following RE mapping of
CSI-RS sequences.
[0016] For X=1, port CSI-RS resource,
a.sub.k,l.sup.(p,.mu.)=.beta..sub.CSIRSw.sub.f(k')w.sub.t(l')r(m')
k=k+k'+12m'
l=l+l'
[0017] For X>1, port CSI-RS resource,
a.sub.k,l.sup.(p,.mu.)=.beta..sub.CSIRSw.sub.f(k')w.sub.t(l')r(2m'+k')
k=k+k'+12m'
l=l+k'
Where m' are integers corresponding to the occupied PRBs. The UE
shall assume .beta..sub.CSIRS>0 for a non-zero-power CSI-RS
where .beta..sub.CSIRS is selected such that the power offset
specified by the higher-layer parameter, if provided, is fulfilled.
The quantities k, k', l', w.sub.f(k'), and w.sub.t(l') are given by
Table1 through Table5,below.
TABLE-US-00001 TABLE 1 CSI-RS locations within a slot. Density Row
Ports .rho. CDMtype (k, l) k' l' 1 1 3 No CDM (k.sub.0, l.sub.0),
(k.sub.0 + 4, l.sub.0), (k.sub.0 + 8, l.sub.0) 0 0 2 1 1, 0.5 No
CDM (k.sub.0, l.sub.0) 0 0 3 2 1, 0.5 FD-CDM2 (k.sub.0, l.sub.0) 0,
1 0 4 4 1 FD-CDM2 (k.sub.0, l.sub.0), (k.sub.0 + 2, l.sub.0) 0, 1 0
5 4 1 FD-CDM2 (k.sub.0, l.sub.0), (k.sub.0, l.sub.0 + 1) 0, 1 0 7 8
1 FD-CDM2 (k.sub.0, l.sub.0), (k.sub.1, l.sub.0), (k.sub.2,
l.sub.0), (k.sub.3, l.sub.0) 0, 1 0 8 8 1 FD-CDM2 (k.sub.0,
l.sub.0), (k.sub.1, l.sub.0), (k.sub.0, l.sub.0 + 1), (k.sub.1,
l.sub.0 + 1) 0, 1 0 9 8 1 CDM4 (FD2, TD2) (k.sub.0, l.sub.0),
(k.sub.1, l.sub.0) 0, 1 0, 1 10 12 1 FD-CDM2 (k.sub.0, l.sub.0),
(k.sub.1, l.sub.0), (k.sub.2, l.sub.0), (k.sub.3, l.sub.0),
(k.sub.4, l.sub.0), (k.sub.5, l.sub.0) 0, 1 0 11 12 1 CDM4 (FD2,
TD2) (k.sub.0, l.sub.0), (k.sub.1, l.sub.0), (k.sub.2, l.sub.0) 0,
1 0, 1 12 16 1, 0.5 FD-CDM2 (k.sub.0, l.sub.0), (k.sub.1, l.sub.0),
(k.sub.2, l.sub.0), (k.sub.3, l.sub.0), (k.sub.0, l.sub.0 + 1), 0,
1 0 (k.sub.1, l.sub.0 + 1), (k.sub.2, l.sub.0 + 1), (k.sub.3,
l.sub.0 + 1) 13 16 1, 0.5 CDM4 (FD2, TD2) (k.sub.0, l.sub.0),
(k.sub.1, l.sub.0), (k.sub.2, l.sub.0), (k.sub.3, l.sub.0) 0, 1 0,
1 14 24 1, 0.5 FD-CDM2 (k.sub.0, l.sub.0), (k.sub.1, l.sub.0),
(k.sub.2, l.sub.0), (k.sub.0, l.sub.0 + 1), (k.sub.1, l.sub.0 + 1),
0, 1 0 (k.sub.2, l.sub.0 + 1), (k.sub.0, l.sub.1), (k.sub.1,
l.sub.1), (k.sub.2, l.sub.1), (k.sub.0, l.sub.1 + 1), (k.sub.1,
l.sub.1 + 1), (k.sub.2, l.sub.1 + 1) 15 24 1, 0.5 CDM4 (FD2, TD2)
(k.sub.0, l.sub.0), (k.sub.1, l.sub.0), (k.sub.2, l.sub.0),
(k.sub.0, l.sub.1), (k.sub.1, l.sub.1), (k.sub.2, l.sub.1) 0, 1 0,
1 16 24 1, 0.5 CDM8 (FD2, TD4) (k.sub.0, l.sub.0), (k.sub.1,
l.sub.0), (k.sub.2, l.sub.0) 0, 1 0, 1, 2, 3 17 32 1, 0.5 FD-CDM2
(k.sub.0, l.sub.0), (k.sub.1, l.sub.0), (k.sub.2, l.sub.0),
(k.sub.3, l.sub.0), (k.sub.0, l.sub.0 + 1), 0, 1 0 (k.sub.1,
l.sub.0 + 1), (k.sub.2, l.sub.0 + 1), (k.sub.3, l.sub.0 + 1),
(k.sub.0, l.sub.1), (k.sub.1, l.sub.1), (k.sub.2, l.sub.1),
(k.sub.3, l.sub.1), (k.sub.0, l.sub.1 + 1), (k.sub.1, l.sub.1 + 1),
(k.sub.2, l.sub.1 + 1), (k.sub.3, l.sub.1 + 1) 18 32 1, 0.5 CDM4
(FD2, TD2) (k.sub.0, l.sub.0), (k.sub.1, l.sub.0), (k.sub.2,
l.sub.0), (k.sub.3, l.sub.0), (k.sub.0, l.sub.1), (k.sub.1,
l.sub.1), 0, 1 0, 1 (k.sub.2, l.sub.1), (k.sub.3, l.sub.1) 19 32 1,
0.5 CDM8 (FD2, TD4) (k.sub.0, l.sub.0), (k.sub.1, l.sub.0),
(k.sub.2, l.sub.0), (k.sub.3, l.sub.0) 0, 1 0, 1, 2, 3
TABLE-US-00002 TABLE 2 The sequences w.sub.f (k') and w.sub.t (l')
for CDMType equal to `no CDM` Index w.sub.f (k') w.sub.t (l') 0 1
1
TABLE-US-00003 TABLE 3 The sequences w.sub.f (k') and w.sub.t (l')
for CDMType equal to `FD-CDM2` Index w.sub.f (k') w.sub.t (l') 0
[+1 +1] 1 1 [+1 -1] 1
TABLE-US-00004 TABLE 4 The sequences w.sub.f (k') and w.sub.t (l')
for CDMType equal to `CDM4` Index w.sub.f (k') w.sub.t (l') 0 [+1
+1] [+1 +1] 1 [+1 -1] [+1 +1] 2 [+1 +1] [+1 -1] 3 [+1 -1] [+1
-1]
TABLE-US-00005 TABLE 5 The sequences w.sub.f (k') and w.sub.t (l')
for CDMType equal to `CDM8` Index w.sub.f (k') w.sub.t (l') 0 [+1
+1] [+1 +1 +1 +1] 1 [+1 -1] [+1 +1 +1 +1] 2 [+1 +1] [+1 -1 +1 -1] 3
[+1 -1] [+1 -1 +1 -1] 4 [+1 +1] [+1 +1 -1 -1] 5 [+1 -1] [+1 +1 -1
-1] 6 [+1 +1] [+1 -1 -1 +1] 7 [+1 -1] [+1 -1 -1 +1]
[0018] Referring now to FIG. 2, a flow diagram of process of
scrambling ID configuration for demodulation reference signals
(DMRS) in accordance with one or more embodiments will be
discussed. As shown in FIG. 2, flow diagram illustrates the
signaling the choice of configured scrambling identifier (ID) to
the user with the following two options. In a first option, the
choice of scrambling ID is configured by transmitting a scrambling
ID configuration 310 from gNB 112 to UE 110 using transmission
configuration indication (TCI) states as part of a synchronization
signal block (SSB) or as part of channel state information
reference signal (CSI-RS) configuration. In a second option, the
choice of scrambling ID is configured by transmitting a scrambling
ID configuration 310 from gNB 112 to UE 110 using explicit downlink
control information (DCI) signaling to select one of the scrambling
IDs. The selected scrambling ID can then be used to transmit DMRS
signals in the physical downlink shared channel (PDSCH) 314 and
physical uplink shared channel (PUSCH) 316 for example for data
demodulation.
DMRS Generation
[0019] For New Radio (NR) Release 15 demodulation reference signal
(DMRS) design, it was agreed in RAN1#91 that the DMRS would be
generated using a length-31 pseudo-random sequence. Pseudo-random
sequences are defined by a length-31 Gold sequence. The output
sequence c(n) of lengthM.sub.PN, where n=0, 1, . . . , M.sub.PN is
defined by
c(n)=(x.sub.1(n+N.sub.C)+x.sub.2(n+N.sub.C))mod 2
x.sub.1(n+31)=(x.sub.1(n+3)+x.sub.1(n))mod 2
x.sub.2(n+31)=.sub.2(n+3)+x.sub.2(n+2)+x.sub.2(n+1)+x.sub.2(n))mod
2
where N.sub.C=1600 and the first m-sequence shall be initialized
with x.sub.1(0)=1, x.sub.1(n)=0, n=1, 2, . . . , 30. The
initialization of the second m-sequence is denoted by c.sub.init
with the value given as follows:
c.sub.init=(2.sup.17(14n.sub.s+l+1)(2N.sub.ID.sup.n.sup.SCID+1)+2N.sub.I-
D.sup.n.sup.SCID+n.sub.SCID)mod 2.sup.31
where n.sub.s is the slot index in the radio frame, l is the OFDM
symbol index and N.sub.ID.sup.n.sup.SCID is the 16-bit scrambling
ID given by the higher layer parameter UL-DMRS-Scrambling-ID or
DL-DMRS-Scrambling-ID for uplink and downlink respectively. The
scrambling is indexed by the 1-bit value n.sub.SCID.di-elect
cons.{0, 1} which is to be signaled to the user for determining the
configured scrambling ID.
Signaling Scrambling ID
[0020] In one embodiment, n.sub.SCID can be configured in the
CSI-RS configuration. In another embodiment, n.sub.SCID can be
configured in the SS-Block. In both embodiments, the actual value
of n.sub.SCID can be signaled using transmission configuration
information (TCI) states if the higher layer parameter
TCI-PresentInDCI is "enabled". In this case, the TCI state is
signaled using 3-bits in the DCI of the ControlResourceSet
(CORESET) scheduling the PDSCH/PUSCH. The value of n.sub.SCID can
be associated with a TCI state which is associated with CSI-RS or
SS-Block configuration.
[0021] In another embodiment when the higher layer parameter
TCI-PresentInDCI is "disabled", there are no TCI bits associated
with the DCI. In this case, the default value of n.sub.SCID can be
set to 0. In yet another embodiment, the value of
n.sub.SCID.di-elect cons.{0, 1} can be signaled to the user using
1-bit in the DCI associated with the CORESET scheduling the
PDSCH/PUSCH for the user.
[0022] Section 7.4.1.1.1 of 3GPP TS 38.211 V15.2.0 (2018-06)
illustrates an example of sequence generation of DMRS signals for
the PDSCH as follows.
7.4.1.1.1 Sequence Generation
[0023] The UE shall assume the sequence r(n) is defined by
r ( n ) = 1 2 ( 1 - 2 c ( 2 n ) ) + j 1 2 ( 1 - 2 c ( 2 n + 1 ) ) .
##EQU00002##
where the pseudo-random sequence c(i) is defined in clause 5.2.1.
The pseudo-random sequence generator shall be initialized with
c.sub.init=(2.sup.17(N.sub.symb.sup.slotn.sub.s,f.sup..mu.+l+1)(2N.sub.I-
D.sup.n.sup.SCID+1)+2N.sub.ID.sup.n.sup.SCID+n.sub.SCID)mod
2.sup.31
where is the OFDM symbol number within the slot, n.sub.s,f.sup..mu.
is the slot number within a frame, and N.sub.ID.sup.0,
N.sub.ID.sup.1.di-elect cons.{0, 1, . . . , 65535} are given by the
higher-layer parameters scramblingID0 and scramblingID1,
respectively, in the DMRS-DownlinkConfig IE if provided and the
PDSCH is scheduled by PDCCH using DCI format 1_1 with the CRC
scrambled by C-RNTI or CS-RNTI; N.sub.ID.sup.0.di-elect cons.{0, 1,
. . . , 65535} is given by the higher-layer parameter scramblingID0
in the DMRS-DownlinkConfig IE if provided and the PDSCH is
scheduled by PDCCH using DCI format 1_0 with the CRC scrambled by
C-RNTI or CS-RNTI; N.sub.ID.sup.n.sup.SCID=N.sub.ID.sup.cell
otherwise;
[0024] The quantity n.sub.SCID.di-elect cons.{0, 1} is given by the
DM-RS sequence initialization field, if present, in the DCI
associated with the PDSCH transmission if DCI format 1_1 in [4, TS
38.212] is used, otherwise n.sub.SCID=0.
[0025] FIG. 3 illustrates an architecture of a system of a network
in accordance with some embodiments. The system 300 is shown to
include a user equipment (UE) 301 and a UE 302. The UEs 301 and 302
are illustrated as smartphones (e.g., handheld touchscreen mobile
computing devices connectable to one or more cellular networks) but
may also comprise any mobile or non-mobile computing device, such
as Personal Data Assistants (PDAs), pagers, laptop computers,
desktop computers, wireless handsets, or any computing device
including a wireless communications interface.
[0026] In some embodiments, any of the UEs 301 and 302 can comprise
an Internet of Things (IoT) UE, which can comprise a network access
layer designed for low-power IoT applications utilizing short-lived
UE connections. An IoT UE can utilize technologies such as
machine-to-machine (M2M) or machine-type communications (MTC) for
exchanging data with an MTC server or device via a public land
mobile network (PLMN), Proximity-Based Service (ProSe) or
device-to-device (D2D) communication, sensor networks, or IoT
networks. The M2M or MTC exchange of data may be a
machine-initiated exchange of data. An IoT network describes
interconnecting IoT UEs, which may include uniquely identifiable
embedded computing devices (within the Internet infrastructure),
with short-lived connections. The IoT UEs may execute background
applications (e.g., keep-alive messages, status updates, etc.) to
facilitate the connections of the IoT network.
[0027] The UEs 301 and 302 may be configured to connect, e.g.,
communicatively couple, with a radio access network (RAN) 310--the
RAN 310 may be, for example, an Evolved Universal Mobile
Telecommunications System (UMTS) Terrestrial Radio Access Network
(E-UTRAN), a NextGen RAN (NG RAN), or some other type of RAN. The
UEs 301 and 302 utilize connections 303 and 304, respectively, each
of which comprises a physical communications interface or layer
(discussed in further detail below); in this example, the
connections 303 and 304 are illustrated as an air interface to
enable communicative coupling, and can be consistent with cellular
communications protocols, such as a Global System for Mobile
Communications (GSM) protocol, a code-division multiple access
(CDMA) network protocol, a Push-to-Talk (PTT) protocol, a PTT over
Cellular (POC) protocol, a Universal Mobile Telecommunications
System (UMTS) protocol, a 3GPP Long Term Evolution (LTE) protocol,
a fifth generation (5G) protocol, a New Radio (NR) protocol, and
the like.
[0028] In this embodiment, the UEs 301 and 302 may further directly
exchange communication data via a ProSe interface 305. The ProSe
interface 305 may alternatively be referred to as a sidelink
interface comprising one or more logical channels, including but
not limited to a Physical Sidelink Control Channel (PSCCH), a
Physical Sidelink Shared Channel (PSSCH), a Physical Sidelink
Discovery Channel (PSDCH), and a Physical Sidelink Broadcast
Channel (PSBCH).
[0029] The UE 302 is shown to be configured to access an access
point (AP) 306 via connection 307. The connection 307 can comprise
a local wireless connection, such as a connection consistent with
any IEEE 802.11 protocol, wherein the AP 306 would comprise a
wireless fidelity (WiFi.RTM.) router. In this example, the AP 306
is shown to be connected to the Internet without connecting to the
core network of the wireless system (described in further detail
below).
[0030] The RAN 310 can include one or more access nodes that enable
the connections 303 and 304. These access nodes (ANs) can be
referred to as base stations (BSs), NodeBs, evolved NodeBs (eNBs),
next Generation NodeBs (gNB), RAN nodes, and so forth, and can
comprise ground stations (e.g., terrestrial access points) or
satellite stations providing coverage within a geographic area
(e.g., a cell). The RAN 310 may include one or more RAN nodes for
providing macrocells, e.g., macro RAN node 311, and one or more RAN
nodes for providing femtocells or picocells (e.g., cells having
smaller coverage areas, smaller user capacity, or higher bandwidth
compared to macrocells), e.g., low power (LP) RAN node 312.
[0031] Any of the RAN nodes 311 and 312 can terminate the air
interface protocol and can be the first point of contact for the
UEs 301 and 302. In some embodiments, any of the RAN nodes 311 and
312 can fulfill various logical functions for the RAN 310
including, but not limited to, radio network controller (RNC)
functions such as radio bearer management, uplink and downlink
dynamic radio resource management and data packet scheduling, and
mobility management.
[0032] In accordance with some embodiments, the UEs 301 and 302 can
be configured to communicate using Orthogonal Frequency-Division
Multiplexing (OFDM) communication signals with each other or with
any of the RAN nodes 311 and 312 over a multicarrier communication
channel in accordance various communication techniques, such as,
but not limited to, an Orthogonal Frequency-Division Multiple
Access (OFDMA) communication technique (e.g., for downlink
communications) or a Single Carrier Frequency Division Multiple
Access (SC-FDMA) communication technique (e.g., for uplink and
ProSe or sidelink communications), although the scope of the
embodiments is not limited in this respect. The OFDM signals can
comprise a plurality of orthogonal subcarriers.
[0033] In some embodiments, a downlink resource grid can be used
for downlink transmissions from any of the RAN nodes 311 and 312 to
the UEs 301 and 302, while uplink transmissions can utilize similar
techniques. The grid can be a time-frequency grid, called a
resource grid or time-frequency resource grid, which is the
physical resource in the downlink in each slot. Such a
time-frequency plane representation is a common practice for OFDM
systems, which makes it intuitive for radio resource allocation.
Each column and each row of the resource grid corresponds to one
OFDM symbol and one OFDM subcarrier, respectively. The duration of
the resource grid in the time domain corresponds to one slot in a
radio frame. The smallest time-frequency unit in a resource grid is
denoted as a resource element. Each resource grid comprises a
number of resource blocks, which describe the mapping of certain
physical channels to resource elements. Each resource block
comprises a collection of resource elements; in the frequency
domain, this may represent the smallest quantity of resources that
currently can be allocated. There are several different physical
downlink channels that are conveyed using such resource blocks.
[0034] The physical downlink shared channel (PDSCH) may carry user
data and higher-layer signaling to the UEs 301 and 302. The
physical downlink control channel (PDCCH) may carry information
about the transport format and resource allocations related to the
PDSCH channel, among other things. It may also inform the UEs 301
and 302 about the transport format, resource allocation, and H-ARQ
(Hybrid Automatic Repeat Request) information related to the uplink
shared channel. Typically, downlink scheduling (assigning control
and shared channel resource blocks to the UE 102 within a cell) may
be performed at any of the RAN nodes 311 and 312 based on channel
quality information fed back from any of the UEs 301 and 302. The
downlink resource assignment information may be sent on the PDCCH
used for (e.g., assigned to) each of the UEs 301 and 302.
[0035] The PDCCH may use control channel elements (CCEs) to convey
the control information. Before being mapped to resource elements,
the PDCCH complex-valued symbols may first be organized into
quadruplets, which may then be permuted using a sub-block
interleaver for rate matching. Each PDCCH may be transmitted using
one or more of these CCEs, where each CCE may correspond to nine
sets of four physical resource elements known as resource element
groups (REGs). Four Quadrature Phase Shift Keying (QPSK) symbols
may be mapped to each REG. The PDCCH can be transmitted using one
or more CCEs, depending on the size of the downlink control
information (DCI) and the channel condition. There can be four or
more different PDCCH formats defined in LTE with different numbers
of CCEs (e.g., aggregation level, L=1, 2, 4, or 8).
[0036] Some embodiments may use concepts for resource allocation
for control channel information that are an extension of the
above-described concepts. For example, some embodiments may utilize
an enhanced physical downlink control channel (EPDCCH) that uses
PDSCH resources for control information transmission. The EPDCCH
may be transmitted using one or more enhanced the control channel
elements (ECCEs). Similar to above, each ECCE may correspond to
nine sets of four physical resource elements known as an enhanced
resource element groups (EREGs). An ECCE may have other numbers of
EREGs in some situations.
[0037] The RAN 310 is shown to be communicatively coupled to a core
network (CN) 320--via an S1 interface 313. In embodiments, the CN
320 may be an evolved packet core (EPC) network, a NextGen Packet
Core (NPC) network, or some other type of CN. In this embodiment
the S1 interface 313 is split into two parts: the S1-U interface
314, which carries traffic data between the RAN nodes 311 and 312
and the serving gateway (S-GW) 322, and the S1-mobility management
entity (MME) interface 315, which is a signaling interface between
the RAN nodes 311 and 312 and MMEs 321.
[0038] In this embodiment, the CN 320 comprises the MMEs 321, the
S-GW 322, the Packet Data Network (PDN) Gateway (P-GW) 323, and a
home subscriber server (HSS) 324. The MMEs 321 may be similar in
function to the control plane of legacy Serving General Packet
Radio Service (GPRS) Support Nodes (SGSN). The MMEs 321 may manage
mobility aspects in access such as gateway selection and tracking
area list management. The HSS 324 may comprise a database for
network users, including subscription-related information to
support the network entities' handling of communication sessions.
The CN 320 may comprise one or several HSSs 324, depending on the
number of mobile subscribers, on the capacity of the equipment, on
the organization of the network, etc. For example, the HSS 324 can
provide support for routing/roaming, authentication, authorization,
naming/addressing resolution, location dependencies, etc.
[0039] The S-GW 322 may terminate the Si interface 313 towards the
RAN 310, and routes data packets between the RAN 310 and the CN
320. In addition, the S-GW 322 may be a local mobility anchor point
for inter-RAN node handovers and also may provide an anchor for
inter-3GPP mobility. Other responsibilities may include lawful
intercept, charging, and some policy enforcement.
[0040] The P-GW 323 may terminate an SGi interface toward a PDN.
The P-GW 323 may route data packets between the EPC network 323 and
external networks such as a network including the application
server 330 (alternatively referred to as application function (AF))
via an Internet Protocol (IP) interface 325. Generally, the
application server 330 may be an element offering applications that
use IP bearer resources with the core network (e.g., UMTS Packet
Services (PS) domain, LTE PS data services, etc.). In this
embodiment, the P-GW 323 is shown to be communicatively coupled to
an application server 330 via an IP communications interface 325.
The application server 330 can also be configured to support one or
more communication services (e.g., Voice-over-Internet Protocol
(VoIP) sessions, PTT sessions, group communication sessions, social
networking services, etc.) for the UEs 301 and 302 via the CN
320.
[0041] The P-GW 323 may further be a node for policy enforcement
and charging data collection. Policy and Charging Enforcement
Function (PCRF) 326 is the policy and charging control element of
the CN 320. In a non-roaming scenario, there may be a single PCRF
in the Home Public Land Mobile Network (HPLMN) associated with a
UE's Internet Protocol Connectivity Access Network (IP-CAN)
session. In a roaming scenario with local breakout of traffic,
there may be two PCRFs associated with a UE's IP-CAN session: a
Home PCRF (H-PCRF) within a HPLMN and a Visited PCRF (V-PCRF)
within a Visited Public Land Mobile Network (VPLMN). The PCRF 326
may be communicatively coupled to the application server 330 via
the P-GW 323. The application server 330 may signal the PCRF 326 to
indicate a new service flow and select the appropriate Quality of
Service (QoS) and charging parameters. The PCRF 326 may provision
this rule into a Policy and Charging Enforcement Function (PCEF)
(not shown) with the appropriate traffic flow template (TFT) and
QoS class of identifier (QCI), which commences the QoS and charging
as specified by the application server 330.
[0042] FIG. 4 illustrates example components of a device in
accordance with some embodiments. In some embodiments, the device
400 may include application circuitry 402, baseband circuitry 404,
Radio Frequency (RF) circuitry 406, front-end module (FEM)
circuitry 408, one or more antennas 410, and power management
circuitry (PMC) 412 coupled together at least as shown. The
components of the illustrated device 400 may be included in a UE or
a RAN node. In some embodiments, the device 400 may include less
elements (e.g., a RAN node may not utilize application circuitry
402, and instead include a processor/controller to process IP data
received from an EPC). In some embodiments, the device 400 may
include additional elements such as, for example, memory/storage,
display, camera, sensor, or input/output (I/O) interface. In other
embodiments, the components described below may be included in more
than one device (e.g., said circuitries may be separately included
in more than one device for Cloud-RAN (C-RAN) implementations).
[0043] The application circuitry 402 may include one or more
application processors. For example, the application circuitry 402
may include circuitry such as, but not limited to, one or more
single-core or multi-core processors. The processor(s) may include
any combination of general-purpose processors and dedicated
processors (e.g., graphics processors, application processors,
etc.). The processors may be coupled with or may include
memory/storage and may be configured to execute instructions stored
in the memory/storage to enable various applications or operating
systems to run on the device 400. In some embodiments, processors
of application circuitry 402 may process IP data packets received
from an EPC.
[0044] The baseband circuitry 404 may include circuitry such as,
but not limited to, one or more single-core or multi-core
processors. The baseband circuitry 404 may include one or more
baseband processors or control logic to process baseband signals
received from a receive signal path of the RF circuitry 406 and to
generate baseband signals for a transmit signal path of the RF
circuitry 406. Baseband processing circuitry 404 may interface with
the application circuitry 402 for generation and processing of the
baseband signals and for controlling operations of the RF circuitry
406. For example, in some embodiments, the baseband circuitry 404
may include a third generation (3G) baseband processor 404A, a
fourth generation (4G) baseband processor 404B, a fifth generation
(5G) baseband processor 404C, or other baseband processor(s) 404D
for other existing generations, generations in development or to be
developed in the future (e.g., second generation (2G), sixth
generation (6G), etc.). The baseband circuitry 404 (e.g., one or
more of baseband processors 404A-D) may handle various radio
control functions that enable communication with one or more radio
networks via the RF circuitry 406. In other embodiments, some or
all of the functionality of baseband processors 404A-D may be
included in modules stored in the memory 404G and executed via a
Central Processing Unit (CPU) 404E. The radio control functions may
include, but are not limited to, signal modulation/demodulation,
encoding/decoding, radio frequency shifting, etc. In some
embodiments, modulation/demodulation circuitry of the baseband
circuitry 404 may include Fast-Fourier Transform (FFT), precoding,
or constellation mapping/demapping functionality. In some
embodiments, encoding/decoding circuitry of the baseband circuitry
404 may include convolution, tail-biting convolution, turbo,
Viterbi, or Low Density Parity Check (LDPC) encoder/decoder
functionality. Embodiments of modulation/demodulation and
encoder/decoder functionality are not limited to these examples and
may include other suitable functionality in other embodiments.
[0045] In some embodiments, the baseband circuitry 404 may include
one or more audio digital signal processor(s) (DSP) 404F. The audio
DSP(s) 404F may be include elements for compression/decompression
and echo cancellation and may include other suitable processing
elements in other embodiments. Components of the baseband circuitry
may be suitably combined in a single chip, a single chipset, or
disposed on a same circuit board in some embodiments. In some
embodiments, some or all of the constituent components of the
baseband circuitry 404 and the application circuitry 402 may be
implemented together such as, for example, on a system on a chip
(SOC).
[0046] In some embodiments, the baseband circuitry 404 may provide
for communication compatible with one or more radio technologies.
For example, in some embodiments, the baseband circuitry 404 may
support communication with an evolved universal terrestrial radio
access network (EUTRAN) or other wireless metropolitan area
networks (WMAN), a wireless local area network (WLAN), a wireless
personal area network (WPAN). Embodiments in which the baseband
circuitry 404 is configured to support radio communications of more
than one wireless protocol may be referred to as multi-mode
baseband circuitry.
[0047] RF circuitry 406 may enable communication with wireless
networks using modulated electromagnetic radiation through a
non-solid medium. In various embodiments, the RF circuitry 406 may
include switches, filters, amplifiers, etc. to facilitate the
communication with the wireless network. RF circuitry 406 may
include a receive signal path which may include circuitry to
down-convert RF signals received from the FEM circuitry 408 and
provide baseband signals to the baseband circuitry 404. RF
circuitry 406 may also include a transmit signal path which may
include circuitry to up-convert baseband signals provided by the
baseband circuitry 404 and provide RF output signals to the FEM
circuitry 408 for transmission.
[0048] In some embodiments, the receive signal path of the RF
circuitry 406 may include mixer circuitry 406a, amplifier circuitry
406b and filter circuitry 406c. In some embodiments, the transmit
signal path of the RF circuitry 406 may include filter circuitry
406c and mixer circuitry 406a. RF circuitry 406 may also include
synthesizer circuitry 406d for synthesizing a frequency for use by
the mixer circuitry 406a of the receive signal path and the
transmit signal path. In some embodiments, the mixer circuitry 406a
of the receive signal path may be configured to down-convert RF
signals received from the FEM circuitry 408 based on the
synthesized frequency provided by synthesizer circuitry 406d. The
amplifier circuitry 406b may be configured to amplify the
down-converted signals and the filter circuitry 406c may be a
low-pass filter (LPF) or band-pass filter (BPF) configured to
remove unwanted signals from the down-converted signals to generate
output baseband signals. Output baseband signals may be provided to
the baseband circuitry 404 for further processing. In some
embodiments, the output baseband signals may be zero-frequency
baseband signals, although this is not a requirement. In some
embodiments, mixer circuitry 406a of the receive signal path may
comprise passive mixers, although the scope of the embodiments is
not limited in this respect.
[0049] In some embodiments, the mixer circuitry 406a of the
transmit signal path may be configured to up-convert input baseband
signals based on the synthesized frequency provided by the
synthesizer circuitry 406d to generate RF output signals for the
FEM circuitry 408. The baseband signals may be provided by the
baseband circuitry 404 and may be filtered by filter circuitry
406c.
[0050] In some embodiments, the mixer circuitry 406a of the receive
signal path and the mixer circuitry 406a of the transmit signal
path may include two or more mixers and may be arranged for
quadrature downconversion and upconversion, respectively. In some
embodiments, the mixer circuitry 406a of the receive signal path
and the mixer circuitry 406a of the transmit signal path may
include two or more mixers and may be arranged for image rejection
(e.g., Hartley image rejection). In some embodiments, the mixer
circuitry 406a of the receive signal path and the mixer circuitry
406a may be arranged for direct downconversion and direct
upconversion, respectively. In some embodiments, the mixer
circuitry 406a of the receive signal path and the mixer circuitry
406a of the transmit signal path may be configured for
super-heterodyne operation.
[0051] In some embodiments, the output baseband signals and the
input baseband signals may be analog baseband signals, although the
scope of the embodiments is not limited in this respect. In some
alternate embodiments, the output baseband signals and the input
baseband signals may be digital baseband signals. In these
alternate embodiments, the RF circuitry 406 may include
analog-to-digital converter (ADC) and digital-to-analog converter
(DAC) circuitry and the baseband circuitry 404 may include a
digital baseband interface to communicate with the RF circuitry
406. In some dual-mode embodiments, a separate radio IC circuitry
may be provided for processing signals for each spectrum, although
the scope of the embodiments is not limited in this respect.
[0052] In some embodiments, the synthesizer circuitry 406d may be a
fractional-N synthesizer or a fractional N/N+1 synthesizer,
although the scope of the embodiments is not limited in this
respect as other types of frequency synthesizers may be suitable.
For example, synthesizer circuitry 406d may be a delta-sigma
synthesizer, a frequency multiplier, or a synthesizer comprising a
phase-locked loop with a frequency divider.
[0053] The synthesizer circuitry 406d may be configured to
synthesize an output frequency for use by the mixer circuitry 406a
of the RF circuitry 406 based on a frequency input and a divider
control input. In some embodiments, the synthesizer circuitry 406d
may be a fractional N/N+1 synthesizer.
[0054] In some embodiments, frequency input may be provided by a
voltage-controlled oscillator (VCO), although that is not a
requirement. Divider control input may be provided by either the
baseband circuitry 404 or the applications processor 402 depending
on the desired output frequency. In some embodiments, a divider
control input (e.g., N) may be determined from a look-up table
based on a channel indicated by the applications processor 402.
[0055] Synthesizer circuitry 406d of the RF circuitry 406 may
include a divider, a delay-locked loop (DLL), a multiplexer and a
phase accumulator. In some embodiments, the divider may be a dual
modulus divider (DMD) and the phase accumulator may be a digital
phase accumulator (DPA). In some embodiments, the DMD may be
configured to divide the input signal by either N or N+1 (e.g.,
based on a carry out) to provide a fractional division ratio. In
some example embodiments, the DLL may include a set of cascaded,
tunable, delay elements, a phase detector, a charge pump and a
D-type flip-flop. In these embodiments, the delay elements may be
configured to break a VCO period up into Nd equal packets of phase,
where Nd is the number of delay elements in the delay line. In this
way, the DLL provides negative feedback to help ensure that the
total delay through the delay line is one VCO cycle.
[0056] In some embodiments, synthesizer circuitry 406d may be
configured to generate a carrier frequency as the output frequency,
while in other embodiments, the output frequency may be a multiple
of the carrier frequency (e.g., twice the carrier frequency, four
times the carrier frequency) and used in conjunction with
quadrature generator and divider circuitry to generate multiple
signals at the carrier frequency with multiple different phases
with respect to each other. In some embodiments, the output
frequency may be a LO frequency (fLO). In some embodiments, the RF
circuitry 406 may include an IQ/polar converter.
[0057] FEM circuitry 408 may include a receive signal path which
may include circuitry configured to operate on RF signals received
from one or more antennas 410, amplify the received signals and
provide the amplified versions of the received signals to the RF
circuitry 406 for further processing. FEM circuitry 408 may also
include a transmit signal path which may include circuitry
configured to amplify signals for transmission provided by the RF
circuitry 406 for transmission by one or more of the one or more
antennas 410. In various embodiments, the amplification through the
transmit or receive signal paths may be done solely in the RF
circuitry 406, solely in the FEM 408, or in both the RF circuitry
406 and the FEM 408.
[0058] In some embodiments, the FEM circuitry 408 may include a
TX/RX switch to switch between transmit mode and receive mode
operation. The FEM circuitry may include a receive signal path and
a transmit signal path. The receive signal path of the FEM
circuitry may include an LNA to amplify received RF signals and
provide the amplified received RF signals as an output (e.g., to
the RF circuitry 406). The transmit signal path of the FEM
circuitry 408 may include a power amplifier (PA) to amplify input
RF signals (e.g., provided by RF circuitry 406), and one or more
filters to generate RF signals for subsequent transmission (e.g.,
by one or more of the one or more antennas 410).
[0059] In some embodiments, the PMC 412 may manage power provided
to the baseband circuitry 404. In particular, the PMC 412 may
control power-source selection, voltage scaling, battery charging,
or DC-to-DC conversion. The PMC 412 may often be included when the
device 400 is capable of being powered by a battery, for example,
when the device is included in a UE. The PMC 412 may increase the
power conversion efficiency while providing desirable
implementation size and heat dissipation characteristics.
[0060] While FIG. 4 shows the PMC 412 coupled only with the
baseband circuitry 404. However, in other embodiments, the PMC 4 12
may be additionally or alternatively coupled with, and perform
similar power management operations for, other components such as,
but not limited to, application circuitry 402, RF circuitry 406, or
FEM 408.
[0061] In some embodiments, the PMC 412 may control, or otherwise
be part of, various power saving mechanisms of the device 400. For
example, if the device 400 is in an RRC_Connected state, where it
is still connected to the RAN node as it expects to receive traffic
shortly, then it may enter a state known as Discontinuous Reception
Mode (DRX) after a period of inactivity. During this state, the
device 400 may power down for brief intervals of time and thus save
power.
[0062] If there is no data traffic activity for an extended period
of time, then the device 400 may transition off to an RRC_Idle
state, where it disconnects from the network and does not perform
operations such as channel quality feedback, handover, etc. The
device 400 goes into a very low power state and it performs paging
where again it periodically wakes up to listen to the network and
then powers down again. The device 400 may not receive data in this
state, in order to receive data, it must transition back to
RRC_Connected state.
[0063] An additional power saving mode may allow a device to be
unavailable to the network for periods longer than a paging
interval (ranging from seconds to a few hours). During this time,
the device is totally unreachable to the network and may power down
completely. Any data sent during this time incurs a large delay and
it is assumed the delay is acceptable.
[0064] Processors of the application circuitry 402 and processors
of the baseband circuitry 404 may be used to execute elements of
one or more instances of a protocol stack. For example, processors
of the baseband circuitry 404, alone or in combination, may be used
execute Layer 3, Layer 2, or Layer 1 functionality, while
processors of the application circuitry 404 may utilize data (e.g.,
packet data) received from these layers and further execute Layer 4
functionality (e.g., transmission communication protocol (TCP) and
user datagram protocol (UDP) layers). As referred to herein, Layer
3 may comprise a radio resource control (RRC) layer, described in
further detail below. As referred to herein, Layer 2 may comprise a
medium access control (MAC) layer, a radio link control (RLC)
layer, and a packet data convergence protocol (PDCP) layer,
described in further detail below. As referred to herein, Layer 1
may comprise a physical (PHY) layer of a UE/RAN node, described in
further detail below.
[0065] FIG. 5 illustrates example interfaces of baseband circuitry
in accordance with some embodiments. As discussed above, the
baseband circuitry 404 of FIG. 4 may comprise processors 404A-404E
and a memory 404G utilized by said processors. Each of the
processors 404A-404E may include a memory interface, 504A-504E,
respectively, to send/receive data to/from the memory 404G.
[0066] The baseband circuitry 404 may further include one or more
interfaces to communicatively couple to other circuitries/devices,
such as a memory interface 512 (e.g., an interface to send/receive
data to/from memory external to the baseband circuitry 404), an
application circuitry interface 514 (e.g., an interface to
send/receive data to/from the application circuitry 402 of FIG. 4),
an RF circuitry interface 516 (e.g., an interface to send/receive
data to/from RF circuitry 406 of FIG. 4), a wireless hardware
connectivity interface 518 (e.g., an interface to send/receive data
to/from Near Field Communication (NFC) components, Bluetooth.RTM.
components (e.g., Bluetooth.RTM. Low Energy), Wi-Fi.RTM.
components, and other communication components), and a power
management interface 520 (e.g., an interface to send/receive power
or control signals to/from the PMC 412.
[0067] In the description herein and/or claims, the terms coupled
and/or connected, along with their derivatives, may be used. In
particular embodiments, connected may be used to indicate that two
or more elements are in direct physical and/or electrical contact
with each other. Coupled may mean that two or more elements are in
direct physical and/or electrical contact. Coupled, however, may
also mean that two or more elements may not be in direct contact
with each other, but yet may still cooperate and/or interact with
each other. For example, "coupled" may mean that two or more
elements do not contact each other but are indirectly joined
together via another element or intermediate elements. Finally, the
terms "on," "overlying," and "over" may be used in the following
description and claims. "On," "overlying," and "over" may be used
to indicate that two or more elements are in direct physical
contact with each other. It should be noted, however, that "over"
may also mean that two or more elements are not in direct contact
with each other. For example, "over" may mean that one element is
above another element but not contact each other and may have
another element or elements in between the two elements.
Furthermore, the term "and/or" may mean "and", it may mean "or", it
may mean "exclusive-or", it may mean "one", it may mean "some, but
not all", it may mean "neither", and/or it may mean "both",
although the scope of claimed subject matter is not limited in this
respect. In the description herein and/or claims, the terms
"comprise" and "include," along with their derivatives, may be used
and are intended as synonyms for each other.
[0068] Although the claimed subject matter has been described with
a certain degree of particularity, it should be recognized that
elements thereof may be altered by persons skilled in the art
without departing from the spirit and/or scope of claimed subject
matter. It is believed that the subject matter pertaining to CSI-RS
sequence generation and mapping and DMRS scrambling ID
configuration and many of its attendant utilities will be
understood by the forgoing description, and it will be apparent
that various changes may be made in the form, construction and/or
arrangement of the components thereof without departing from the
scope and/or spirit of the claimed subject matter or without
sacrificing all of its material advantages, the form herein before
described being merely an explanatory embodiment thereof, and/or
further without providing substantial change thereto. It is the
intention of the claims to encompass and/or include such
changes.
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