U.S. patent application number 14/874582 was filed with the patent office on 2016-01-28 for speed frame exchange within single user, multiple user, multiple access, and/or mimo wireless communications.
This patent application is currently assigned to BROADCOM CORPORATION. The applicant listed for this patent is BROADCOM CORPORATION. Invention is credited to Matthew James Fischer, Chiu Ngok Eric Wong.
Application Number | 20160029380 14/874582 |
Document ID | / |
Family ID | 50928708 |
Filed Date | 2016-01-28 |
United States Patent
Application |
20160029380 |
Kind Code |
A1 |
Wong; Chiu Ngok Eric ; et
al. |
January 28, 2016 |
Speed frame exchange within single user, multiple user, multiple
access, and/or MIMO wireless communications
Abstract
A signaling protocol allows for speed frame exchange between
different wireless communication devices within single user,
multiple user, multiple access, and/or MIMO wireless communication
system. A listening wireless communication device analyzes state of
speed frame indicator bits within frames transmitted from a first
other wireless communication device to determine the entire radio
frame exchanges between that first other wireless communication
device and a second other wireless communication device. The second
other wireless communication device may be a hidden node relative
to the listening wireless communication device such that all or
less than all transmissions from the hidden node are received by
the listening device. The listening wireless communication device
determines the status of the communication medium (e.g., the air in
the context of a wireless communication system), so that it can
transmit successfully without interfering with any ongoing
communications between the first and second other wireless
communication devices.
Inventors: |
Wong; Chiu Ngok Eric; (San
Jose, CA) ; Fischer; Matthew James; (Mountain View,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BROADCOM CORPORATION |
IRVINE |
CA |
US |
|
|
Assignee: |
BROADCOM CORPORATION
IRVINE
CA
|
Family ID: |
50928708 |
Appl. No.: |
14/874582 |
Filed: |
October 5, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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13930813 |
Jun 28, 2013 |
9155102 |
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14874582 |
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61747438 |
Dec 31, 2012 |
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61828247 |
May 29, 2013 |
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Current U.S.
Class: |
370/336 |
Current CPC
Class: |
H04W 72/0473 20130101;
H04W 72/1205 20130101; H04W 74/0808 20130101; H04W 72/0446
20130101; H04W 84/18 20130101 |
International
Class: |
H04W 72/04 20060101
H04W072/04 |
Claims
1. A wireless communication device comprising: a processor
configured to: transmit first one or more frames to a first other
wireless communication device, wherein first one or more frames
includes information for interpretation by a second other wireless
communication device that is out of range of the first other
wireless communication device to determine when the first other
wireless communication device is likely transmitting second one or
more frames to the wireless communication device; and receive the
second one or more frames from the first other wireless
communication device.
2. The wireless communication device of claim 1, wherein the
processor is further configured to: transmit the first one or more
frames to the first other wireless communication device, wherein
first one or more frames includes the information for
interpretation by the second other wireless communication device
that is out of range of the first other wireless communication
device also to determine at least one characteristic of
communication between the wireless communication device and the
first other wireless communication device.
3. The wireless communication device of claim 2, wherein the at
least one characteristic of communication between the wireless
communication device and the first other wireless communication
device includes at least one of: a single frame exchange between
the wireless communication device and the first other wireless
communication device; symmetrical multiple frame exchanges between
the wireless communication device and the first other wireless
communication device; asymmetrical multiple frame exchanges between
the wireless communication device and the first other wireless
communication device; frame length of at least one frame
transmitted by the first other wireless communication device to the
wireless communication device; channel allocation of at least one
communication channel between the wireless communication device and
the first other wireless communication device; or transmit power of
at least one of the wireless communication device or the first
other wireless communication device.
4. The wireless communication device of claim 1, wherein the
information within the first one or more frames for interpretation
by the second other wireless communication device that is out of
range of the first other wireless communication device includes
state of a predetermined at least one bit contained within the
first one or more frames.
5. The wireless communication device of claim 4, wherein the
predetermined at least one bit including at least one of a more
data bit field, an acknowledgement indication bit field, or one
media access control (MAC) header bit and two physical layer (PHY)
header bits.
6. The wireless communication device of claim 4, wherein state of
the predetermined at least one bit indicating at least one of an
additional frame to be transmitted, a last frame to be transmitted,
a type of frame being transmitted, or reservation of a
communication medium for some period of time.
7. The wireless communication device of claim 1, wherein the second
other wireless communication device includes a smart meter station
(SMSTA).
8. The wireless communication device of claim 1 further comprising:
an access point (AP), wherein the first other wireless
communication device includes a wireless station (STA).
9. A wireless communication device comprising: a processor
configured to: receive first one or more frames from a first other
wireless communication device, wherein first one or more frames
includes information for interpretation by a second other wireless
communication device that is out of range of the wireless
communication device to determine when the wireless communication
device is likely transmitting second one or more frames to the
first wireless communication device; and transmit the second one or
more frames to the first other wireless communication device.
10. The wireless communication device of claim 9, wherein the
processor is further configured to: receive the first one or more
frames to the first other wireless communication device, wherein
first one or more frames includes the information for
interpretation by the second other wireless communication device
that is out of range of the wireless communication device also to
determine at least one characteristic of communication between the
wireless communication device and the first other wireless
communication device.
11. The wireless communication device of claim 10, wherein the at
least one characteristic of communication between the wireless
communication device and the first other wireless communication
device includes at least one of: a single frame exchange between
the wireless communication device and the first other wireless
communication device; symmetrical multiple frame exchanges between
the wireless communication device and the first other wireless
communication device; asymmetrical multiple frame exchanges between
the wireless communication device and the first other wireless
communication device; frame length of at least one frame
transmitted by the first other wireless communication device to the
wireless communication device; channel allocation of at least one
communication channel between the wireless communication device and
the first other wireless communication device; or transmit power of
at least one of the wireless communication device or the first
other wireless communication device.
12. The wireless communication device of claim 9, wherein the
information within the first one or more frames for interpretation
by the second other wireless communication device that is out of
range of the wireless communication device includes state of a
predetermined at least one bit contained within the first one or
more frames.
13. The wireless communication device of claim 12, wherein the
predetermined at least one bit including at least one of a more
data bit field, an acknowledgement indication bit field, or one
media access control (MAC) header bit and two physical layer (PHY)
header bits.
14. The wireless communication device of claim 12, wherein state of
the predetermined at least one bit indicating at least one of an
additional frame to be transmitted, a last frame to be transmitted,
a type of frame being transmitted, or reservation of a
communication medium for some period of time.
15. The wireless communication device of claim 9 further
comprising: a wireless station (STA), wherein the first other
wireless communication device includes an access point (AP), and
the second other wireless communication device includes a smart
meter station (SMSTA).
16. A method for execution by a wireless communication device, the
method comprising: transmitting, via a communication interface of
the wireless communication device, first one or more frames to a
first other wireless communication device, wherein first one or
more frames includes information for interpretation by a second
other wireless communication device that is out of range of the
first other wireless communication device to determine when the
first other wireless communication device is likely transmitting
second one or more frames to the wireless communication device; and
receiving, via the communication interface of the wireless
communication device, the second one or more frames from the first
other wireless communication device.
17. The method of claim 16 further comprising: transmitting, via
the communication interface of the wireless communication device,
the first one or more frames to the first other wireless
communication device, wherein first one or more frames includes the
information for interpretation by the second other wireless
communication device that is out of range of the first other
wireless communication device also to determine at least one
characteristic of communication between the wireless communication
device and the first other wireless communication device, wherein
the at least one characteristic of communication between the
wireless communication device and the first other wireless
communication device includes at least one of: a single frame
exchange between the wireless communication device and the first
other wireless communication device; symmetrical multiple frame
exchanges between the wireless communication device and the first
other wireless communication device; asymmetrical multiple frame
exchanges between the wireless communication device and the first
other wireless communication device; frame length of at least one
frame transmitted by the first other wireless communication device
to the wireless communication device; channel allocation of at
least one communication channel between the wireless communication
device and the first other wireless communication device; or
transmit power of at least one of the wireless communication device
or the first other wireless communication device.
18. The method of claim 16, wherein the information within the
first one or more frames for interpretation by the second other
wireless communication device that is out of range of the first
other wireless communication device includes state of a
predetermined at least one bit contained within the first one or
more frames.
19. The method of claim 18, wherein the predetermined at least one
bit including at least one of a more data bit field, an
acknowledgement indication bit field, or one media access control
(MAC) header bit and two physical layer (PHY) header bits.
20. The method of claim 18, wherein state of the predetermined at
least one bit indicating at least one of an additional frame to be
transmitted, a last frame to be transmitted, a type of frame being
transmitted, or reservation of a communication medium for some
period of time.
Description
CROSS REFERENCE TO RELATED PATENTS/PATENT APPLICATIONS
[0001] The present U.S. Utility patent application claims priority
pursuant to 35 U.S.C. .sctn.120 as a continuation of U.S. Utility
application Ser. No. 13/930,813, entitled "Speed frame exchange
within single user, multiple user, multiple access, and/or MIMO
wireless communications," filed Jun. 28, 2013, pending, and
scheduled subsequently to be issued as U.S. Pat. No. 9,155,102 on
Oct. 6, 2015 (as indicated in an ISSUE NOTIFICATION mailed from the
USPTO on Sep. 16, 2015), which claims priority pursuant to 35
U.S.C. .sctn.119(e) to U.S. Provisional Application No. 61/747,438,
entitled "Speed frame exchange within single user, multiple user,
multiple access, and/or MIMO wireless communications," filed Dec.
31, 2012, and U.S. Provisional Patent Application Ser. No.
61/828,247, entitled "Speed frame exchange within single user,
multiple user, multiple access, and/or MIMO wireless
communications," filed May 29, 2013; all of which are hereby
incorporated herein by reference in their entirety and made part of
the present U.S. Utility patent application for all purposes.
DESCRIPTION OF RELATED ART
[0002] Communication systems support wireless and wire lined
communications between wireless and/or wire lined communication
devices. The systems can range from national and/or international
cellular telephone systems, to the Internet, to point-to-point
in-home wireless networks and can operate in accordance with one or
more communication standards. For example, wireless communication
systems may operate in accordance with one or more standards
including, but not limited to, IEEE 802.11x (where x may be various
extensions such as a, b, n, g, etc.), Bluetooth, advanced mobile
phone services (AMPS), digital AMPS, global system for mobile
communications (GSM), etc., and/or variations thereof.
[0003] In some instances, wireless communication is made between a
transmitter (TX) and receiver (RX) using single-output-single-input
(SISO) communication. Another type of wireless communication is
single-input-multiple-output (SIMO) in which a single TX processes
data into RF signals that are transmitted to a RX that includes two
or more antennae and two or more RX paths.
[0004] Yet an alternative type of wireless communication is
multiple-input-single-output (MISO) in which a TX includes two or
more transmission paths that each respectively converts a
corresponding portion of baseband signals into RF signals, which
are transmitted via corresponding antennae to a RX. Another type of
wireless communication is multiple-input-multiple-output (MIMO) in
which a TX and RX each respectively includes multiple paths such
that a TX parallel processes data using a spatial and time encoding
function to produce two or more streams of data and a RX receives
the multiple RF signals via multiple RX paths that recapture the
streams of data utilizing a spatial and time decoding function.
[0005] A device within such a wireless communication system may
able to receive or listen to transmissions from a first device that
communicates with a second device yet is unable to receive or
listen to transmissions from the second device. Without a clear
indication of the status of the communication medium (e.g., air in
the context of a wireless communication system), different devices
may inadvertently attempt communications at the same time resulting
in collisions, lost packets, etc.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0006] FIG. 1 is a diagram illustrating one or more embodiments of
a wireless communication system.
[0007] FIG. 2 is a diagram illustrating an embodiment of a number
of wireless communication devices, some operative as smart meter
stations (SMSTAs).
[0008] FIG. 3 is a diagram illustrating an example of communication
between two wireless communication devices with another wireless
communication device being able to receive one side of the
communication.
[0009] FIG. 4 is a diagram illustrating an example of a frame in
accordance with the present disclosure.
[0010] FIG. 5 is a diagram illustrating an example of a timing
diagram of communication between two wireless communication
devices.
[0011] FIG. 6 is a diagram illustrating another example of a timing
diagram of communication between two wireless communication
devices.
[0012] FIG. 7 is a diagram illustrating another example of a timing
diagram of communication between two wireless communication
devices.
[0013] FIG. 8 is a diagram illustrating another example of a timing
diagram of communication between two respective wireless
communication devices.
[0014] FIG. 9 is a diagram illustrating another example of a timing
diagram of communication between two wireless communication
devices.
[0015] FIG. 10 is a diagram illustrating an embodiment of a method
for execution by a first wireless communication device.
DETAILED DESCRIPTION
[0016] FIG. 1 is a diagram illustrating one or more embodiments of
a wireless communication system 100. The wireless communication
system 100 includes base stations and/or access points 112-116,
wireless communication devices 118-132 (e.g., devices that include
wireless stations (STAs) and/or stand-alone wireless stations),
smart meter station (SMSTA) 190 and 191, and a network hardware
component 134. The wireless communication devices 118-132 may be
laptop computers, or tablets, 118 and 126, personal digital
assistant 120 and 130, personal computer 124 and 132 and/or
cellular telephone 122 and 128. The details of an embodiment of
such wireless communication devices are described in greater detail
with reference to FIG. 2.
[0017] The base stations (BSs) or access points (APs) 112-116 are
operably coupled to the network hardware 134 via local area network
connections 136, 138, and 140. The network hardware 134, which may
be a router, switch, bridge, modem, system controller, etc.,
provides a wide area network connection 142 for the communication
system 100. Each of the base stations or access points 112-116 has
an associated antenna or antenna array to communicate with the
wireless communication devices in its area. Typically, the wireless
communication devices register with a particular base station or
access point 112-114 to receive services from the communication
system 100. For direct connections (i.e., point-to-point
communications), wireless communication devices communicate
directly via an allocated channel.
[0018] Within such a wireless communication system 100, a wireless
communication device may be able to detect or listen to one side of
a communication between two other wireless communication devices.
That is to say, the wireless communication device may be able to
listen to receive or listen to transmissions from a first device
but not from a second device, which is out of range, or hidden
(e.g., a hidden node), from the wireless communication device. The
second device may be out of range or hidden for various reasons
(e.g., due to distance between the wireless communication device
and the second device, an interferer (e.g., building, hill, etc.)
blocking the wireless communication device's ability to receive
transmissions of the second device, or fading or null spots within
a communication system). When a wireless communication device is
able to listen to one-side of a communication but not the other
side, the wireless communication device determines when the other
side of the communication is likely being transmitted based on what
it can receive to avoid collisions, packets losses, and/or other
adverse effects on the wireless communication system.
[0019] FIG. 2 is a diagram illustrating an embodiment 200 of a
number of wireless communication devices, some operative as smart
meter stations (SMSTAs). The SMSTA are implemented in various
locations in an environment including a building or structure. Some
wireless communication devices may be implemented to support
communications associated with monitoring and/or sensing of any of
a variety of different conditions, parameters, etc. Such wireless
communication devices provide such sensed/monitored information to
one or more other wireless communication devices (e.g., from the
SMSTAs to an AP).
[0020] A SMSTA has communication functionality similar to a
wireless station (STA) and is also operative to perform
communication of monitoring and/or sensing related information. In
certain applications, such devices may operate only very rarely.
For example, when compared to the periods of time in which such a
device is in power savings mode (e.g., a sleep mode, a reduced
functionality operational mode a lowered power operational mode,
etc.), the operational periods of time may be miniscule in
comparison (e.g., only a few percentage of the periods of time in
which the device is in such a power savings mode).
[0021] An SMSTA may awaken from such a power savings mode only to
perform certain operations. For example, such a device may awaken
from such a power savings mode to perform sensing and/or
measurement of one or more parameters, conditions, constraints,
etc. During such an operational period (e.g., in which the device
is not in a power savings mode), the device may transmit such
information to another wireless communication device (e.g., an
access point (AP), another SMSTA, a wireless station (STA), or such
an SMSTA or STA operating as an AP, etc.).
[0022] In an SMSTA environment, multiple respective wireless
communication devices (e.g., SMSTAs) can be implemented to forward
monitoring and/or sensing related information to one particular
wireless communication device that operates as a manager,
coordinator, etc. such as may be implemented by an access point
(AP) or a wireless station (STA) operating as an AP. Such SMSTAs
may be implemented to perform any of a number of data forwarding,
monitoring and/or sensing operations. For example, in the context
of a building or structure, there may be a number of services that
are provided to that building or structure, including natural gas
service, electrical service, television service, Internet service,
etc. Alternatively, different respective monitors and/or sensors
may be implemented throughout the environment to perform monitoring
and/or sensing related to parameters not specifically related to
services. As some examples, motion detection, door ajar detection,
temperature measurement (and/or other atmospheric and/or
environmental measurements), etc. may be performed by different
respective monitors and/or sensors implemented in various locations
and for various purposes. Communications from SMSTAs may be very
important and yet performed quite infrequently. When communications
from SMSTAs are not received by the manager, coordinator, etc.
wireless communication device, one or more systems that use such
monitoring and/or sensing information suffer performance
degradation.
[0023] A processor within a given wireless communication device
(e.g., a first wireless communication device) is configured to
identify frame exchanges between two other wireless communication
devices, even when one of them is a hidden node. Even when
communications from only one of the other wireless communication
devices are received, determination of the frame exchanges between
those devices may be inferred based upon state of speed frame
indicator bits within those frames which are received. Also, if one
or more frames transmitted from the hidden node are somehow
detected, that information may also be used to determine the frame
exchanges between those devices.
[0024] The listening SMSTA determines the frame exchanges between
such devices, one of which may be a hidden node, and may then
determine the communication medium's status (e.g., knowing that
other devices are not currently making transmissions, and the
communication medium is available). For example, the state of such
speed frame indicator bits may indicate various information
including an additional frame to be transmitted, a last frame to be
transmitted, a type of frame being transmitted, reservation of the
communication medium for some period of time, etc. As mentioned
above, the speed frame indicator bits may be partitioned between a
packet's physical layer (PHY) header and a media access control
(MAC) header. The listening SMSTA analyzes of the speed frame
indicator bits's status, including their transition and change
among the various frames that are received, and may then
appropriately determine the status of the communication medium. The
listening SMSTA may transmissions during times in which the
communication medium is available and not being used by other
wireless communication devices.
[0025] FIG. 3 is a diagram illustrating an example 300 of
communication between two wireless communication devices with
another wireless communication device being able to receive one
side of the communication. The listening wireless communication
device able to receive one side of the communication is shown as
1.sup.st wireless communication device 310 and includes a
communication interface 320 to perform transmitting and receiving
of one or more frames (e.g., using a transmitter 322 and a receiver
324). The 1.sup.st wireless communication device 310 also includes
a processor 330, and an associated memory 340, to execute various
operations including interpreting one or more frames transmitted
from at least one of a 2.sup.nd wireless communication device 370
and a 3.sup.rd wireless communication device 380. This frame
interpretation can include analysis of speed frame indicator bits
within the one or more frames.
[0026] For instance, assume that the 2.sup.nd wireless
communication device 370 has a first radiation pattern 351 and is
in communication with the 3.sup.rd wireless communication device
380 that has a second radiation pattern 352. The communication may
be occurring over one or more communication channels in accordance
with one or more wireless communication protocols.
[0027] The 1.sup.st wireless communication device 310 is within the
radiation pattern 351 of the 2.sup.nd wireless communication device
370 but outside of the radiation pattern 352 of the 3.sup.rd
wireless communication device 380. As such, the 1.sup.st wireless
communication device 310 can hear (e.g., receive) transmissions of
the 2.sup.nd wireless communication device 370 but cannot hear
(e.g., receive or accurately recover) at least some of the
transmissions of the 3.sup.rd wireless communication device 380.
Thus, the 3.sup.rd wireless communication device 380 is essentially
hidden (e.g., a hidden device or node) from the 1.sup.st wireless
communication device 310.
[0028] In this situation, to avoid transmission collisions, loss of
packets, and/or other adverse effects on the wireless communication
system, the 1.sup.st wireless communication device 310 determines
when the 3.sup.rd wireless communication device 380 is likely
transmitting based on the transmissions it can receive from the
2.sup.nd wireless communication device 370. Note that the 1.sup.st
wireless communication device 310 may receive limited transmissions
from the 3.sup.rd wireless communication device 380 and further use
that information to determine when the 3.sup.rd wireless
communication device 380 is likely transmitting.
[0029] As a more specific example, the 1.sup.st wireless
communication device 310 interprets frames transmitted by the
2.sup.nd wireless communication device 370 to determine
characteristics of communication between the 2.sup.nd wireless
communication device 370 and the 3.sup.rd wireless communication
device 380 (e.g., frame(s) 391 from the 2.sup.nd wireless
communication device 370 and/or frame(s) 390 from the 3.sup.rd
wireless communication device). The 1.sup.st wireless communication
device 310 then determines when the 3.sup.rd wireless communication
device 380 is likely transmitting based on the characteristics of
communication. For example, the 1.sup.st wireless communication
device 310 interprets speed frame indicator bits contained within
one or more of the received frames (e.g., frame(s) 390) to
determine when the 3.sup.rd wireless communication device 380 will
likely be transmitting. The 1.sup.st wireless communication device
310 then determines that the one or more communication channels are
unavailable when the 2.sup.nd wireless communication device is
likely transmitting (e.g., such as when transmitting the frame(s)
391).
[0030] As another example, communication of frames (e.g., the
frame(s) 390 and/or the frame(s) 391) between the 2.sup.nd wireless
communication device 370 and the 3.sup.rd wireless communication
device 380 are based on a protocol that sets state of speed frame
indicator bits within those frames. The 1.sup.st wireless
communication device 310 (e.g., listening device) analyzes the
state of the speed frame indicator bits to determine frame
exchanges between the 2.sup.nd wireless communication device 370
and the 3.sup.rd wireless communication device 380. Note that the
speed frame indicator bits may be included within any number of
types of frames communicated between devices. The state of such
speed frame indicator bits may indicate various characteristics of
the communication between the devices including an additional frame
to be transmitted, a last frame to be transmitted, a type of frame
being transmitted, reservation of the communication medium for some
period of time, etc. For example, characteristics of the
communication between the 2.sup.nd wireless communication device
370 and the 3.sup.rd wireless communication device 380 may be a
single frame exchange, symmetrical or asymmetrical multiple frame
exchanges, frame length of the a frame transmitted by one of these
wireless communication devices, channel allocation of the
communication channel between the devices, transmit power of one or
both of the wireless communication devices, etc. Further note that
the speed frame indicator bits may be partitioned between a
packet's physical layer (PHY) header and a media access control
(MAC) header.
[0031] Even when transmissions are received from only one of the
2.sup.nd wireless communication device 370 or the 3.sup.rd wireless
communication device 380, the 1.sup.st wireless communication
device 310 (e.g., listening device) may fill in missing frame
exchanges between the 2.sup.nd wireless communication device 370 or
the 3.sup.rd wireless communication device 380 based on the state
of the speed frame indicator bits. The state of the speed frame
indicator bits may change as the frames are transmitted. In this
instance, the 1.sup.st wireless communication device 310 determines
one or more frames transmitted from the hidden node device (e.g.,
the 2.sup.nd wireless communication device 370 or the 3.sup.rd
wireless communication device 380) as well as determines when
communications between the 2.sup.nd wireless communication device
370 and the 3.sup.rd wireless communication device 380 are
completed. With such knowledge of other devices' communications,
even when they cannot be directly received, the 1.sup.st wireless
communication device 310 can make transmissions with a high
expectation of success.
[0032] FIG. 4 is a diagram illustrating an example 400 of a frame
in accordance with the present disclosure. Generally speaking, a
frame may be transmitted from one wireless communication device
(e.g., device 124 of FIG. 1) to another wireless communication
device (e.g., BS or AP 114 of FIG. 1). Such a frame includes a
physical layer (PHY) header and one or more media access control
(MAC) frames. A PHY header may include a number of respective
fields such as one or more short training fields (STFs) and one or
more long training fields (LTFs) which may be used for channel
characterization and estimation, a signal field (SIG) which may be
used for synchronization and other purposes, and the PHY header may
also include other respective fields.
[0033] The general format of a MAC frame includes the following
basic components: media access control (MAC) header, a frame body,
and a frame check sequence (FCS). In certain embodiments, the MAC
header includes fields for each of frame control (FC), duration
(DUR/ID), address (e.g., receiver and/or transmitter addresses),
sequence control information, optional Quality of Service (QoS)
Control information (e.g., for QoS data frames only), and HT
Control fields (+HTC frames only) (optional fields). Note that such
a signal and frame structure is illustrative and provided as an
example, and alternative embodiments of signal and frame structures
may also be employed.
[0034] The frame includes speed frame indicator bits partitioned
among the PHY header and the MAC header. The SIG within the PHY
header includes an acknowledgment indication (AckInd) bit field
(e.g., 2 bits), and the FC field of the MAC header includes a more
data (MD) field (e.g., 1 bit). These three bits serve as the speed
frame indicator bits within the communication protocol presented in
this disclosure. A listening wireless communication device is able
to detect or hear frames transmitted from only one of two other
wireless communication device in communication (e.g., detect
frame(s) transmitted by device 124 but unable to detect frame(s)
transmitted by BS or AP 114 of FIG. 1).
[0035] State of the MD field may be used to indicate uplink data.
In certain prior communication protocols, the MD field indicates
more downlink data. For example, The MD field indicates buffered
data at one wireless communication device (e.g., AP) intended for
another wireless communication device (e.g., STA, SMSTA, etc.) in a
power save operational mode (in a DATA frame). Alternatively, the
MD field indicates the one wireless communication device (e.g., AP)
has one or more pending transmissions if an automatic power save
delivery (APSD) operative wireless communication device (e.g.,
APSD-STA) advertises support for MD acknowledgement (in an
acknowledgement (ACK) frame). In even another situation, the MD
field indicates the TDLS (Tunneled Direct Link Setup) peer wireless
communication device (e.g., STA) has pending transmissions. Also,
within a group-addressed DATA frame, the MD field indicates more
broadcast or multicast frames will be buffered at another wireless
communication device (e.g., AP). Also, the MD field may serve
another purpose including indication of uplink data.
[0036] Various timing diagrams are presented and described below.
For illustration, communications are shown as occurring between an
access point (AP) and a wireless station (STA). However, such
communications may generally be performed between any two wireless
communication devices (e.g., AP to AP, STA to STA, STA to AP, AP to
STA, SMSTA to AP, AP to SMSTA, etc.). There are a large number of
possible frame exchanges that may occur between two respective
wireless communication devices, and the following timing diagrams
are examples to illustrate the functionality of such a protocol.
Any number of variations or alternative frame exchanges may be
employed in other implementations, examples, and/or
embodiments.
[0037] A listening wireless communication device (e.g., another
wireless communication device) may determine the communications
between the AP and the STA interpreting the one or more frames to
determine characteristics of communication between the AP and the
STA (even when one of them is a hidden node). For example, consider
the STA is a hidden node, then a listening wireless communication
device determine when the STA is likely transmitting based on the
characteristics of communication transmitted from the AP. The
listening wireless communication device then will indicate that a
communication channel is unavailable when the STA is likely
transmitting and can also indicate that the communication channel
is available when neither the STA nor the AP is likely
transmitting. FIG. 5 through FIG. 9 show various examples of how a
listening wireless communication device is implemented to determine
communications between two other wireless communication devices
based on analysis of speed frame indicator bits within one or more
frames transmitted from only one of the two other wireless
communication devices (e.g., only the AP or the STA). In these
examples below, the speed frame indicator bits include an
acknowledgment indication (AckInd) bit field (e.g., 2 bits) within
the SIG within the PHY header's SIG, and the more data (MD) field
(e.g., 1 bit) within the MAC header's FC field).
[0038] FIG. 5 is a diagram illustrating an example 500 of a timing
diagram of communication between two wireless communication
devices. In this diagram, a STA awakens from a reduced power state
or a sleep state (e.g., at a scheduled wake time) and after a probe
delay, transmits data to the AP with the MD bit set to 1 and the
AckInd bits set to 00. In this diagram, the STA includes buffered
uplink traffic, and starts transmission with uplink data instead of
PS-POLL. When this uplink data is transmitted, the STA does not
necessarily have information regarding whether or not the AP has
data intended for the STA. As such, the AckInd bits set to 00, and
a default setting of the AckInd bits to 00 may be made when a given
device does not have information regarding status of data within
the other device. The MD bit set to 1 to indicate that the STA has
additional data to be transmitted to the AP. Also, in this diagram,
the MD bit is used to allow the responder (AP) to set the AckInd
bits correctly in a subsequent frame.
[0039] Then, after a short interframe space (SIFS), the AP
transmits an acknowledgment (ACK) to the STA with the MD bit set to
1 and the AckInd bits set to 11. Because of the indication of the
MD in the uplink communication, the AP knows that additional data
will be transmitted from the STA. The MD bit set to 1 to indicate
that the AP will make an additional transmission to the STA, and
the AckInd bits set to 11 reserve the communication medium for the
next transmission from the STA. That is to say, the AckInd bits set
to 11 reserve the communication medium for a period of time to
allow the subsequent transmission from the STA to the AP.
[0040] Then, after another SIFS, the STA transmits the additional
data to the AP with MD bit set to 0 and the AckInd bits set to 00.
The MD bit set to 1 to indicate that the STA does not have
additional data to be transmitted to the AP. The AckInd bits set to
00 indicate that an ACK is requested from the AP.
[0041] Then after another SIFS, the AP transmits another ACK to the
STA with the MD bit set to 0 and the AckInd bits set to 10. The MD
bit set to 0 to indicate that the AP will not make an additional
transmission to the STA, and the AckInd bits set to 10 indicate
that no response in needed from the STA. Subsequently, the STA will
return to a reduced power or sleep state sends the MD bit was set
to 0 in the latest ACK, and the STA will understand that no
additional communications will be received from the AP.
[0042] FIG. 6 is a diagram illustrating another example 600 of a
timing diagram of communication between two wireless communication
devices. In this diagram, both the AP and the STA have an equal
number of uplink and downlink data frames to be exchanged. Also,
since the AP is aware of the STA's wake time, the AP can prepare
downlink data for the STA. As with the prior diagram, the STA
starts transmission with uplink data instead of PS-POLL.
[0043] After awakening from the reduced power or sleep state, the
STA transmits a data frame with the MD bit set to 1 and the AckInd
bits set to 00 (e.g., default setting without knowledge of the AP).
The MD bit set to 1 to indicate that the STA will make an
additional transmission to the AP.
[0044] Then, after a SIFS, the AP transmits a data frame with the
MD bit set to 1 and the AckInd bits set to 11. The MD bit set to 1
to indicate that the AP will make an additional transmission to the
STA, and the AckInd bits set to 11 reserve the communication medium
for the next transmission from the STA. Any number of additional
data frame exchanges may occur between the STA and the AP.
[0045] Continuing on, the AP transmits a data frame with the MD bit
set to 1 and the AckInd bits set to 11. The MD bit set to 1 to
indicate that the AP will make an additional transmission to the
STA, and the AckInd bits set to 11 reserve the communication medium
for the next transmission from the AP.
[0046] After an SIFS, the AP transmits a data frame with the MD bit
set to 1 and the AckInd bits set to 11. The MD bit set to 1 to
indicate that the STA will make an additional transmission to the
AP, and the AckInd bits set to 11 reserve the communication medium
for the next transmission from the AP.
[0047] Then, after yet another an SIFS, the STA transmits a data
frame with the MD bit set to 0 and the AckInd bits set to 11. This
particular transmission may include a block acknowledgement
(BlockACK or BA) inside of an aggregated MAC (media access control)
data protocol unit (A-MPDU) with DATA. The MD bit set to 0 to
indicate that the STA will not make an additional transmission to
the AP (e.g., this is the last data frame from the STA), and the
AckInd bits set to 11 reserve the communication medium for the next
transmission from the AP.
[0048] After yet another an SIFS, the AP transmits a data frame
with the MD bit set to 0 and the AckInd bits set to 00. The MD bit
set to 0 to indicate that the AP will not make an additional
transmission to the AP (e.g., this is the last data frame from the
AP), and the AckInd bits set to 00 to indicate that an ACK is
requested from the STA.
[0049] After the final SIFS in this frame exchange, the STA
transmits an acknowledgement (ACK) frame with the MD bit set to 0
and the AckInd bits set to 10. The MD bit set to 0 to indicate that
the STA will not make an additional transmission to the AP after
this ACK, and the AckInd bits set to 10 to indicate that no
response in needed from the AP.
[0050] FIG. 7 is a diagram illustrating another example 700 of a
timing diagram of communication between two wireless communication
devices. The operation of this diagram has some similarities to the
previous two diagrams accept that a beacon is transmitted from the
AP to the STA after the STA has awakened from a reduced power sleep
state. A traffic indication map (TIM) bit within the beacon
provides indication that the AP has buffered downlink data intended
for the STA. As such, in the first data transmission from the STA
to the AP, the STA sets MD bit set to 1 and the AckInd bits set to
11. That is to say, because there's prior knowledge of downlink
data buffered at the AP and intended for the STA, the STA sets the
AckInd bits to 11.
[0051] Then, after a SIFS, the AP transmits a data frame with the
MD bit set to 1 and the AckInd bits set to 11. The MD bit set to 1
to indicate that the AP will make an additional transmission to the
STA, and the AckInd bits set to 11 reserve the communication medium
for the next transmission from the STA. Any number of additional
data frame exchanges may occur between the STA and the AP.
[0052] Continuing on, the AP transmits a data frame with the MD bit
set to 0 and the AckInd bits set to 11. The MD bit set to 1 to
indicate that the AP will not make an additional data frame
transmission to the STA, and the AckInd bits set to 11 reserve the
communication medium for the next transmission from the AP. The
AckInd bits set to 00 indicate that an ACK is requested from the
AP.
[0053] After yet another SIFS, the AP transmits an acknowledgment
(ACK) to the STA with the MD bit set to 0 and the AckInd bits set
to 11. The MD bit set to 1 to indicate that the AP does not have an
additional data for the STA. The AckInd bits set to 11 reserve the
communication medium for the next transmission from the STA.
[0054] Then, after another SIFS, the STA transmits the additional
data to the AP with MD bit set to 0 and the AckInd bits set to 00.
The MD bit set to 1 to indicate that the STA does not have
additional data to be transmitted to the AP. The AckInd bits set to
00 indicate that an ACK is requested from the AP.
[0055] Then after another SIFS, the AP transmits another ACK to the
STA with the MD bit set to 0 and the AckInd bits set to 10. The MD
bit set to 0 to indicate that the AP will not make an additional
transmission to the STA, and the AckInd bits set to 10 indicate
that no response in needed from the STA. Subsequently, the STA will
return to a reduced power or sleep state sends the MD bit was set
to 0 in the latest ACK, and the STA will understand that no
additional communications will be received from the AP. The STA may
then return to the reduced power or sleep state since the last MD
bit from the AP was set to 0.
[0056] FIG. 8 is a diagram illustrating another example 800 of a
timing diagram of communication between two respective wireless
communication devices. In this diagram, after awakening from a low
powered or sleep state, the STA starts transmission with PS-POLL,
instead of uplink data, with the MD bit set to 1 (to indicate
additional buffered uplink data) and the AckInd bits set to 00.
[0057] Then, after SIFS, the AP transmits an acknowledgment (ACK,
shown as A in the diagram) to the STA with the MD bit set to 0 (AP
does not have an additional data for the STA) and the AckInd bits
set to 11 (reserves the communication medium for the next
transmission from the STA).
[0058] The STA makes a subsequent data transmission, and the AP
provides an acknowledgement with the respective MD and AckInd bits
set as indicated in the diagram. Then, after another SIFS, the STA
transmits additional data to the AP with MD bit set to 0 and the
AckInd bits set to 00. The MD bit set to 1 to indicate that the STA
does not have additional data to be transmitted to the AP. The
AckInd bits set to 00 indicate that an ACK is requested from the
AP.
[0059] After an SIFS, the AP then transmits an acknowledgment frame
to the STA with the MD bit set to 1 and the AckInd bits set to 11.
However, in this instance, because the MD bit of the prior data
frame received from the STA is 0, the AP may continue to use the
transmission opportunity (TXOP) and transmit additional downlink
data to the STA. As can be seen, after another SIFS, instead of the
AP receiving a frame from the STA, the AP transmits another data
frame to the STA with MD bit set to 0 (AP does not have an
additional data for the STA) and the AckInd bits set to 00 (an ACK
is requested from the STA).
[0060] Then, after the final SIFS in this frame exchange, the STA
transmits an acknowledgement (ACK) frame with the MD bit set to 0
(STA will not make an additional transmission to the AP after this
ACK) and the AckInd bits set to 10 (no response in needed from the
AP). The STA may then return to the reduced power or sleep state
since the last MD bit from the AP was set to 0.
[0061] FIG. 9 is a diagram illustrating another example 900 of a
timing diagram of communication between two wireless communication
devices. This diagram shows the downlink bufferable unit (BU)
procedure in the context of fewer frame exchanges. In this diagram,
after awakening from a low powered or sleep state, the STA starts
transmission with PS-POLL, accompanied with uplink data, with the
MD bit set to 0 (to indicate the STA does not have additional
buffered uplink data) and the AckInd bits set to 00. After
awakening, the STA may wait either for a probe delay or an enhanced
distributed channel access (EDCA) delay after an AP-assisted
synchronization frame before transmitting the PS-POLL/DATA
frame.
[0062] After an SIFS, the AP then transmits an acknowledgment frame
to the STA with the MD bit set to 1 and the AckInd bits set to 11.
However, in this instance, because the MD bit of the prior data
frame received from the STA is 0, the AP may continue to use the
TXOP and transmit additional downlink data to the STA. As can be
seen, after another SIFS, instead of the AP receiving a frame from
the STA, the AP transmits another data frame to the STA with MD bit
set to 0 (AP does not have an additional data for the STA) and the
AckInd bits set to 00 (an ACK is requested from the STA).
[0063] Then, after the final SIFS in this frame exchange, the STA
transmits an acknowledgement (ACK) frame with the MD bit set to 0
(STA will not make an additional transmission to the AP after this
ACK) and the AckInd bits set to 10 (no response in needed from the
AP). The STA may then return to the reduced power or sleep state
since the last MD bit from the AP was set to 0.
[0064] With respect to the PS-Poll for downlink (DL) procedure, for
speed frame exchange, when the AP receives a frame from the STA
with MD set to 0, and the AP has remaining buffered data for the
STA, then, the AP may indicate one of the following based on this
downlink bufferable unit (BU) procedure:
[0065] 1. More Data to 1, acknowledgment indication (AckInd) to 11
in ACK, and the STA shall stay awake for downlink transmissions
from 1.sup.st wireless communication device (e.g., AP) after
SIFS.
[0066] 2. More Data to 1, AckInd to 10 in ACK, and the STA shall
stay awake until AP sends downlink transmissions.
[0067] 3. More Data to 0, AckInd to 10 in ACK, and STA may go back
to sleep.
[0068] As may be seen, a novel frame exchange approach and
associated protocol has been presented that is compatible with
existing receive operation for a wireless communication device
(e.g., a STA or SMSTA which may operate in a power savings (PS)
mode). Also, this protocol is compatible with other frame exchanges
which may be used based on communication protocols, standards, and
recommended practices. Within such an approach, there are no
separate wake times for polling and data delivery exchanges for
power conscious wireless communication devices (e.g., STAs). Also,
this approach allows for relatively simple wireless communication
device implementation and design (e.g., for the AP) since there is
no need for separate schedules for polling and DATA
transmissions.
[0069] There are various embodiments by which the protocol
described herein may be implemented. For example, with respect to
the assignment of the acknowledgement indicator (AckInd) bits, the
various examples provided above are based upon the assignment shown
in the table on the lower left portion of FIG. 9. However,
alternative assignments may be employed in other embodiments. For
example, table on the lower right portion of FIG. 9 may
alternatively be used. If desired, even other AckInd bits may be
employed to provide effective signaling to other wireless
communication devices within a communication system of the frame
exchanges being performed between the first and second wireless
communication device, even if one of them is a hidden node such
that some or all of the transmissions made from the hidden node are
not received by a listening device.
[0070] Referring to the table on the lower right portion of FIG. 9,
it is noted that an NDP Response (AckInd bits set to 01) may be
used to represent all null data packet (NDP) frames (including NDP
ACK, and NDP BA), and Normal Response (AckInd bits set to 10) may
be used to represent both normal ACK and normal BA.
[0071] FIG. 10 is a diagram illustrating an embodiment of a method
1000 for execution by a first wireless communication device. The
method 1000 begins at step 1010 with the first communication device
receiving, via a communication interface, one or more frames
transmitted from a second wireless communication device. The second
wireless communication device is in communication with a third
wireless communication device, but the first communication device
may not receive at least some of the frames transmitted by the
third wireless communication device. In some instances, the first
wireless communication device receives none of the frames
transmitted from the third communication device. For example, the
third wireless communication device may be a hidden node from the
perspective of the first wireless communication device.
[0072] The method 1000 continues at step 1020 where the first
wireless communication device determines state of speed frame
indicator bits within the received frames. These frame indicator
bits may be partitioned between a packet's physical layer (PHY)
header and a media access control (MAC) header such as described
with reference to FIG. 4.
[0073] The method 1000 continues at step 1030 where the first
wireless communication device identifies frame exchanges between
the second wireless communication device and the third wireless
communication device based on the state of the speed frame
indicator bits. Even if a frame transmitted from the third wireless
communication device is not received by the first wireless
communication device, the first wireless communication device can
identify one or more frames exchanged between the second and third
wireless communication devices based on state of the speed frame
indicator bits within the frames received from the second wireless
communication device.
[0074] It is noted that the various operations and functions
described within various methods herein may be performed within a
wireless communication device (e.g., such as by the baseband
processing module, processing module, or processor 330 and a
communication interface 320 such as described with reference to
FIG. 3) and/or other components therein. Generally, a communication
interface and processor in a wireless communication device can
perform such operations.
[0075] Examples of some components may include one of more baseband
processing modules, one or more media access control (MAC) layers,
one or more physical layers (PHYs), and/or other components, etc.
For example, such a baseband processing module (sometimes in
conjunction with a radio, analog front end (AFE), etc.) can
generate such signals, frames, etc. as described herein as well as
perform various operations described herein and/or their respective
equivalents.
[0076] In some embodiments, such a baseband processing module
and/or a processing module (which may be implemented in the same
device or separate devices) can perform such processing to generate
signals for transmission to another wireless communication device
using any number of radios and antennae. In some embodiments, such
processing is performed cooperatively by a processor in a first
device and another processor within a second device. In other
embodiments, such processing is performed wholly by a processor
within one device.
[0077] The present invention has been described herein with
reference to at least one embodiment. Such embodiment(s) of the
present invention have been described with the aid of structural
components illustrating physical and/or logical components and with
the aid of method steps illustrating the performance of specified
functions and relationships thereof. The boundaries and sequence of
these functional building blocks and method steps have been
arbitrarily defined herein for convenience of description.
Alternate boundaries and sequences can be defined so long as the
specified functions and relationships are appropriately performed.
Any such alternate boundaries or sequences are thus within the
scope and spirit of the claims that follow. Further, the boundaries
of these functional building blocks have been arbitrarily defined
for convenience of description. Alternate boundaries could be
defined as long as the certain significant functions are
appropriately performed. Similarly, flow diagram blocks may also
have been arbitrarily defined herein to illustrate certain
significant functionality. To the extent used, the flow diagram
block boundaries and sequence could have been defined otherwise and
still perform the certain significant functionality. Such alternate
definitions of both functional building blocks and flow diagram
blocks and sequences are thus within the scope and spirit of the
claimed invention. One of average skill in the art will also
recognize that the functional building blocks, and other
illustrative blocks, modules and components herein, can be
implemented as illustrated or by discrete components, application
specific integrated circuits, processors executing appropriate
software and the like or any combination thereof.
[0078] As may also be used herein, the terms "processing module,"
"processing circuit," "processing circuitry," "processing unit"
and/or "processor" may be a single processing device or a plurality
of processing devices. Such a processing device may be a
microprocessor, micro-controller, digital signal processor,
microcomputer, central processing unit, field programmable gate
array, programmable logic device, state machine, logic circuitry,
analog circuitry, digital circuitry, and/or any device that
manipulates signals (analog and/or digital) based on hard coding of
the circuitry and/or operational instructions. The processing
module, module, processing circuit, and/or processing unit may be,
or further include, memory and/or an integrated memory element,
which may be a single memory device, a plurality of memory devices,
and/or embedded circuitry of another processing module, module,
processing circuit, and/or processing unit. Such a memory device
may be a read-only memory, random access memory, volatile memory,
non-volatile memory, static memory, dynamic memory, flash memory,
cache memory, and/or any device that stores digital information.
Note that if the processing module, module, processing circuit,
and/or processing unit includes more than one processing device,
the processing devices may be centrally located (e.g., directly
coupled together via a wired and/or wireless bus structure) or may
be distributedly located (e.g., cloud computing via indirect
coupling via a local area network and/or a wide area network).
Further note that if the processing module, module, processing
circuit, and/or processing unit implements one or more of its
functions via a state machine, analog circuitry, digital circuitry,
and/or logic circuitry, the memory and/or memory element storing
the corresponding operational instructions may be embedded within,
or external to, the circuitry comprising the state machine, analog
circuitry, digital circuitry, and/or logic circuitry. Still further
note that, the memory element may store, and the processing module,
module, processing circuit, and/or processing unit executes, hard
coded and/or operational instructions corresponding to at least
some of the steps and/or functions illustrated in one or more of
the Figures. Such a memory device or memory element can be included
in an article of manufacture.
[0079] As may also be used herein, the term(s) "configured to",
"operably coupled to", "coupled to", and/or "coupling" includes
direct coupling between items and/or indirect coupling between
items via an intervening item (e.g., an item includes, but is not
limited to, a component, an element, a circuit, and/or a module)
where, for an example of indirect coupling, the intervening item
does not modify the information of a signal but may adjust its
current level, voltage level, and/or power level. As may further be
used herein, inferred coupling (i.e., where one element is coupled
to another element by inference) includes direct and indirect
coupling between two items in the same manner as "coupled to". As
may even further be used herein, the term "configured to",
"operable to", "coupled to", or "operably coupled to" indicates
that an item includes one or more of power connections, input(s),
output(s), etc., to perform, when activated, one or more its
corresponding functions and may further include inferred coupling
to one or more other items. As may still further be used herein,
the term "associated with", includes direct and/or indirect
coupling of separate items and/or one item being embedded within
another item.
[0080] Unless specifically stated to the contra, signals to, from,
and/or between elements in a figure of any of the figures presented
herein may be analog or digital, continuous time or discrete time,
and single-ended or differential. For instance, if a signal path is
shown as a single-ended path, it also represents a differential
signal path. Similarly, if a signal path is shown as a differential
path, it also represents a single-ended signal path. While one or
more particular architectures are described herein, other
architectures can likewise be implemented that use one or more data
buses not expressly shown, direct connectivity between elements,
and/or indirect coupling between other elements as recognized by
one of average skill in the art.
[0081] The term "module" is used in the description of one or more
of the embodiments. A module includes a processing module, a
functional block, hardware, and/or software stored on memory for
performing one or more functions as may be described herein. Note
that, if the module is implemented via hardware, the hardware may
operate independently and/or in conjunction with software and/or
firmware. As also used herein, a module may contain one or more
sub-modules, each of which may be one or more modules.
[0082] While particular combinations of various functions and
features of the one or more embodiments have been expressly
described herein, other combinations of these features and
functions are likewise possible. The present disclosure of an
invention is not limited by the particular examples disclosed
herein and expressly incorporates these other combinations.
* * * * *