U.S. patent application number 16/014631 was filed with the patent office on 2018-11-01 for communications when encountering aggressive communication systems.
The applicant listed for this patent is CABLE TELEVISION LABORATORIES, INC.. Invention is credited to JENNIFER ANDREOLI-FANG, ALIREZA BABAEI.
Application Number | 20180317102 16/014631 |
Document ID | / |
Family ID | 58690141 |
Filed Date | 2018-11-01 |
United States Patent
Application |
20180317102 |
Kind Code |
A1 |
BABAEI; ALIREZA ; et
al. |
November 1, 2018 |
COMMUNICATIONS WHEN ENCOUNTERING AGGRESSIVE COMMUNICATION
SYSTEMS
Abstract
Systems and methods presented herein provide for improving
communications when encountering aggressive communication systems.
In one embodiment, a communication system includes a WAP operable
to link a UE to a communication network via a communication
protocol and a communications processor operable with the WAP to
detect another communication system operating within a range of the
WAP, and to determine that the other communication system is
operating via another communication protocol that differs from the
communication protocol of the communication network based on UEs in
range of the WAP. The UEs are operable to communicate via both
communication protocols. The communications processor queries the
UEs in the range of the WAP to determine which of the UEs are
communicating via the other communication protocol, and estimates a
rate of successful communication with the UE via the WAP based on a
number of UEs communicating via the other communication
protocol.
Inventors: |
BABAEI; ALIREZA; (San Jose,
CA) ; ANDREOLI-FANG; JENNIFER; (Boulder, CO) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CABLE TELEVISION LABORATORIES, INC. |
Louisville |
CO |
US |
|
|
Family ID: |
58690141 |
Appl. No.: |
16/014631 |
Filed: |
June 21, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
14940850 |
Nov 13, 2015 |
10009777 |
|
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16014631 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W 24/02 20130101;
H04W 24/10 20130101; H04W 16/14 20130101 |
International
Class: |
H04W 24/02 20090101
H04W024/02; H04W 24/10 20090101 H04W024/10 |
Claims
1. A communication system operable when encountering aggressive
communications, the communication system comprising: a wireless
access point (WAP) operable to link a first user equipment (UE) to
a communication network via a communication protocol; and a
communications processor operable with the WAP to detect another
communication system operating within a range of the WAP, and to
determine that the other communication system is operating via
another communication protocol that differs from the communication
protocol of the communication network based on one or more UEs in
range of the WAP, wherein the one or more UEs are operable to
communicate via both communication protocols and wherein the
communications processor is further operable to query the one or
more UEs in the range of the WAP to determine which of the one or
more UEs are communicating with the other communication system via
the other communication protocol, and to estimate a rate of
successful communication with the first UE via the WAP based on a
number of the one or more UEs communicating via the other
communication protocol.
2. The communication system of claim 1, wherein: the WAP is
operable to link the first UE to the communication network in an
unlicensed band of frequency spectrum.
3. The communication system of claim 1, wherein: the unlicensed
band comprises the Industrial, Scientific, and Medical (ISM) band
of frequency spectrum.
4. The communication system of claim 1, wherein: the communication
protocol of the communication network is a WiFi protocol and the
communication protocol of the other communication system is a Long
Term Evolution (LTE) protocol.
5. The communication system of claim 1, wherein: the WAP is further
operable to direct the UEs to report back the number of the one or
more UEs in vicinity of the WAP and the other communication
system.
6. The communication system of claim 1, wherein: the WAP is further
operable to detect a Long Term Evolution (LTE) capability of a UE
when the UE attempts to connect to the WAP; and the communication
processor is further operable to determine the number of the one or
more UEs in vicinity of the WAP and the other communication system
based on the connection attempts by the UEs.
7. The communication system of claim 1, wherein: the communication
processor is further operable to compare a probability of
successful communication with the first UE to a baseline
probability of successful communication to determine that the other
communication system is behaving aggressively.
8. A method operable within a communication system when
encountering aggressive communications, the method comprising:
linking a first user equipment (UE) to a communication network
through a wireless access point (WAP) via a communication protocol;
detecting another communication system operating within a range of
the WAP; determining that the other communication system is
operating via another communication protocol that differs from the
communication protocol of the communication network based on one or
more UEs in range of the WAP, wherein the one or more UEs are
operable to communicate via both communication protocols; querying
the one or more UEs in the range of the WAP to determine which of
the one or more UEs are communicating with the other communication
system via the other communication protocol; and estimating a rate
of successful communication with the first UE via the WAP based on
a number of the one or more UEs communicating via the other
communication protocol.
9. The method of claim 8, wherein: linking a first UE to a
communication network comprises linking the first UE to the
communication network in an unlicensed band of frequency
spectrum.
10. The method of claim 9, wherein: the unlicensed band comprises
the Industrial, Scientific, and Medical (ISM) band of frequency
spectrum.
11. The method of claim 8, wherein: the communication protocol of
the communication network is a WiFi protocol and the communication
protocol of the other communication system is a Long Term Evolution
(LTE) protocol.
12. The method of claim 8, further comprising: directing the UEs to
report back the number of the one or more UEs in vicinity of the
WAP and the other communication system.
13. The method of claim 8, further comprising: detecting a Long
Term Evolution (LTE) capability of a UE when the UE attempts to
connect to the WAP; and determining the number of the one or more
UEs in vicinity of the WAP and the other communication system based
on the connection attempts by the UEs.
14. The method of claim 8, further comprising: comparing a
probability of successful communication with the first UE to a
baseline probability of successful communication to determine that
the other communication system is behaving aggressively.
15. A non-transitory computer readable medium comprising
instructions that, when executed by a communication processor
operable within a communication system encountering aggressive
communications, directs the communication processor to: link a
first user equipment (UE) to a communication network through a
wireless access point (WAP) via a communication protocol; detect
another communication system operating within a range of the WAP;
determine that the other communication system is operating via
another communication protocol that differs from the communication
protocol of the communication network based on one or more UEs in
range of the WAP, wherein the one or more UEs are operable to
communicate via both communication protocols; query the one or more
UEs in the range of the WAP to determine which of the one or more
UEs are communicating with the other communication system via the
other communication protocol; and estimate a rate of successful
communication with the first UE via the WAP based on a number of
the one or more UEs communicating via the other communication
protocol.
16. The computer readable medium of claim 15, wherein the
instructions that direct the communication processor to link the
first UE to a communication network further comprise instructions
that: direct the communication processor the first UE to the
communication network in an unlicensed band of frequency
spectrum.
17. The computer readable medium of claim 15, wherein: the
communication protocol of the communication network is a WiFi
protocol and the communication protocol of the other communication
system is a Long Term Evolution (LTE) protocol.
18. The computer readable medium of claim 15, further comprising
instructions that direct the communication processor to: direct the
UEs to report back the number of the one or more UEs in vicinity of
the WAP and the other communication system.
19. The computer readable medium of claim 15, further comprising
instructions that direct the communication processor to: detect a
Long Term Evolution (LTE) capability of a UE when the UE attempts
to connect to the WAP; and determine the number of the one or more
UEs in vicinity of the WAP and the other communication system based
on the connection attempts by the UEs.
20. The computer readable medium of claim 15, further comprising
instructions that direct the communication processor to: compare a
probability of successful communication with the first UE to a
baseline probability of successful communication to determine that
the other communication system is behaving aggressively.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 14/940,850, filed Nov. 13, 2015, the
disclosure of which is incorporated in its entirety by reference
herein.
BACKGROUND
[0002] Communication systems exist in a variety of forms operating
at numerous frequency ranges. For example, in North America,
frequency ranges for Long Term Evolution (LTE) networks operate at
700, 750, 800, 850, 1900, 1700, 2100, 2500 and 2600 MHz. These
frequency ranges correspond to government licensed bands of 2, 4,
7, 12, 13, 17, 25, 26, and 41, respectively. In these bands, the
Federal Communications Commission (FCC), a government licensing
authority, assures that communication networks do not interfere
with one another. In other bands, such as the ISM (industrial,
scientific and medical) bands, government licensing agencies
generally allow communications systems to operate freely because
interference between communication systems at these much higher
frequency ranges is often limited by distance. However, some
communications systems are finding themselves in relatively close
proximity with one another at these frequencies, leading to a
competition for radio frequency (RF) resources. Accordingly, some
of these communication systems, such as WiFi, have developed
protocols that ensure each system shares resources fairly.
[0003] Unfortunately, not all of these communication technologies
share the same fairness and resource allocation policies. For
example, as the government licensed the bands to LTE networks,
there was no need for the technology to adopt any type of spectrum
sharing policies because each network had sole use of its frequency
band. Accordingly, when LTE communication systems invade other
unlicensed spectrums, they tend to occupy all of the frequency
resources of the spectrums and interfere with other communication
systems.
SUMMARY
[0004] Systems and methods presented herein provide for improving
communications when encountering aggressive communication systems.
In one embodiment, a communication system includes a wireless
access point (WAP) operable to link a first user equipment (UE) to
a communication network via a communication protocol. The
communication system also includes a communications processor
operable with the WAP to detect another communication system
operating within a range of the WAP, and to determine that the
other communication system is operating via another communication
protocol that differs from the communication protocol of the
communication network based on one or more UEs in range of the WAP.
The UEs are operable to communicate via both communication
protocols. The communications processor is further operable to
query the UEs in the range of the WAP to determine which of the UEs
are communicating with the other communication system via the other
communication protocol, and to estimate a rate of successful
communication with the first UE via the WAP based on a number of
the UEs communicating via the other communication protocol.
[0005] The various embodiments disclosed herein may be implemented
in a variety of ways as a matter of design choice. For example,
some embodiments herein are implemented in hardware whereas other
embodiments may include processes that are operable to implement
and/or operate the hardware. Other exemplary embodiments, including
software and firmware, are described below.
BRIEF DESCRIPTION OF THE FIGURES
[0006] Some embodiments of the present invention are now described,
by way of example only, and with reference to the accompanying
drawings. The same reference number represents the same element or
the same type of element on all drawings.
[0007] FIG. 1 is a block diagram of an exemplary communication
system operable when encountering aggressive behavior from other
communication systems.
[0008] FIG. 2 is a flowchart illustrating an exemplary process of
the communication system of FIG. 1.
[0009] FIG. 3 is a graph illustrating communication success rates
when an LTE network is within range of a WiFi Network.
[0010] FIG. 4 is a graph illustrating a baseline collision
probability when an LTE network is within range of a WiFi
Network.
[0011] FIG. 5 is a block diagram of a WiFi communication system
operable when encountering aggressive behavior from an LTE
communication system.
[0012] FIG. 6 is a block diagram illustrating how a WiFi WAP groups
UEs for contention free access.
[0013] FIGS. 7 and 8 are block diagrams of data frames illustrating
bits for use in messaging a UE.
[0014] FIG. 9 is a flowchart illustrating an exemplary process of
the communication system of FIG. 5.
[0015] FIG. 10 is a block diagram of an exemplary computing system
in which a computer readable medium provides instructions for
performing methods herein.
DETAILED DESCRIPTION OF THE FIGURES
[0016] The figures and the following description illustrate
specific exemplary embodiments of the invention. It will thus be
appreciated that those skilled in the art will be able to devise
various arrangements that, although not explicitly described or
shown herein, embody the principles of the invention and are
included within the scope of the invention. Furthermore, any
examples described herein are intended to aid in understanding the
principles of the invention and are to be construed as being
without limitation to such specifically recited examples and
conditions. As a result, the invention is not limited to the
specific embodiments or examples described below.
[0017] FIG. 1 is a block diagram of an exemplary communication
system operable when encountering aggressive behavior from other
communication systems. The communication system includes a
communication processor 110 that is coupled to a WAP 104 through a
communication network 105. The communication processor 110 is
operable to detect aggressive behavior from the radio access
network (RAN) point 102 communicating with one or more the UEs
103-1 -103-N in the vicinity of the WAP 103. For example, the UE
103-1 may be communicating with the communication network 105
through the WAP 104 under one communication protocol. Other UEs 103
in the area may be communicating with the RAN point 102 via another
different communication protocol. Communications from these other
UEs 103 with the RAN point 102 may interfere with the
communications of UEs 103 trying to communicate through the WAP
104. The communication processor 110 is operable to detect this
aggressive activity and estimate a rate of successful communication
with a UE (e.g., UE 103-1) via the WAP 104 based on some of the UEs
103 (e.g., UEs 103-2-103-N, wherein the reference number "N" is
merely intended to represent an integer greater than 1 and not
necessarily equal to any other "N" references herein) communicating
with the RAN point 102 via the other communication protocol.
[0018] Examples of the UEs 103 include cellular phones, laptop
computers, tablet computers, and the like. Generally, the WAP 104
operates on one protocol and the RAN point 102 operates on another
different protocol. However, the communication processor 110 may
also be operable to detect aggressive activity in an RF band from
another communication system using the same communication protocol
as the WAP 104. In any case, the communication processor 110 is
operable to detect aggressive activity by another communication
system, determine the ability of the UE 103 to communicate through
the WAP 104, and circumvent the aggressive activity of the other
communication system. Examples of the communication processor 110
include network elements operable with the communication network
105 (e.g., communication switches, routers, network servers, etc.).
Although the communication processor 110 was discussed as being
configured external to the WAP 104, alternative embodiments include
the communication processor 110 being configured with the WAP
104.
[0019] Examples of the communication system include a WiFi network
being interfered with by an LTE network. For example, LTE
communications are increasingly moving into unlicensed RF bands
where WiFi communications predominately exist (e.g., the ISM band).
Accordingly, the embodiments herein may be operable to detect
aggressive activity by an LTE network and work to overcome any
interference by the LTE network. However, the invention is not
intended to be limited to WiFi communications being interfered with
by LTE communications. Rather, the embodiments herein are intended
to provide an understanding of how one communication system
operating under a communication protocol can work to overcome
aggressive activity by another communication system operating under
a different communication protocol. Other exemplary embodiments are
shown and described below.
[0020] FIG. 2 is a flowchart illustrating an exemplary process 200
of the communication system of FIG. 1. In this embodiment, the WAP
104 links a first UE 103 (e.g., UE 103-1) to the communication
network 105 using a first communication protocol, in the process
element 201. From there, the communication processor 110 detects
another communication system operating within range of the WAP 104,
in the process element 202. The communication processor 110 then
determines whether the other communication system is operating on
the same protocol as that of the WAP 104, in the process element
203.
[0021] For example, if the WAP 104 is part of a WiFi communication
network using the 802.11 IEEE protocol and the RAN point 102 is
operating under the same WiFi protocol, then the WAP 104
understands how to communicate with the UE 103-1 based on
contention procedures within the 802.11 IEEE protocol so that both
WiFi networks can coexist. However, if the RAN point 102 is part of
an LTE network, the LTE network may attempt to acquire as much of
the RF band as it needs without regard to any other systems, such
as WiFi. And, since the WAP 104 would not understand how to coexist
with another communication network, the LTE communications may
severely degrade or even destroy any possibility of the WAP 104
communicating with the UE 103-1.
[0022] Accordingly, if the other communication system is operating
in accordance with the protocol signaling of the WAP 104, then the
WAP 104 may implement its "back off" procedures to ensure that the
WAP 104 coexists with the RAN 102, in the process element 206. From
there, the WAP 104 and the communication processor 110 may link
another or the same UE 103 to the WAP 104 in the process element
201. That is, the communication processor 110 may continually
evaluate whether communications are likely to be successful for the
UEs 103. But, if the RAN 102 is operating on a different
communication protocol than the WAP 104 so as to potentially
interfere with the WAP 104, then the communication processor 110
queries the UEs 103 within range of the WAP 104, in the process
element 204. From there, the communication processor 110 estimates
a successful communication with the first UE 103 (e.g., the UE
103-1), in the process element 205, based on the number of UEs 103
communicating via the other communication protocol.
[0023] To illustrate, LTE-U (also known as Licensed-Assisted Access
LTE, or "LAA-LTE") is a form of LTE communications in the
unlicensed band. And, this form of communications is being rapidly
implemented so as to provide LTE "hotspots" for subscriber UEs 103.
Although WiFi networks have traditionally been the dominant
technology utilizing the unlicensed spectrum, the advent of LTE-U
will likely change the manner in which the "free" spectrum is
occupied. WiFi traditionally coexists well with other WiFi networks
due to the standardized, contention-based MAC (media access
control) protocol that is implemented by most WiFi equipment. The
DCF (distributed coordinated function) and the EDCA (enhanced
distributed channel access) of the MAC ensures when multiple WiFi
networks occupy the same spectrum in the vicinity of each other so
as to ensure that each network shares the resources fairly.
[0024] LTE on the other hand is a different Radio Access Technology
(RAT) that uses a different channel access algorithm that can
aggressively occupy a channel in an RF band, potentially
interfering with any neighboring WiFi access points. Using the
baseline behavior of DCF/EDCA MAC, WiFi equipment can be configured
to detect aggressive behavior of other users of the unlicensed band
in the vicinity without any changes to the existing MAC protocol
implementations at the WAP 104 and/or in the UEs 103 themselves.
Once aggressive behavior is detected, the communication processor
110 can then determine how to ensure the performance of WiFi
communications with the UE 103 are not adversely harmed through
channel reservation of the LTE network.
[0025] Consider a WiFi network with one WAP and "N" number of
users. The WAP of the WiFi network may detect the presence of
another RAN via UEs 103 that are capable of decoding multiple radio
access technologies, such as WiFi and LTE. In doing so, the WiFi
network (e.g., communication processor 110 and the WAP 104)
estimates the number of UEs 103 associated with the WiFi network
and the number of UEs 103 associated with the LTE network.
[0026] In one embodiment, the communication processor 110 directs
the UEs 103 to turn on their LTE radios to detect a number of their
LTE neighbors and report back to the WAP 104. The UEs 103 may also
report the MAC addresses of their LTE neighbors back to the WAP
104. Based on a union of MAC addresses of LTE neighbors reported by
the UEs 103, the communication processor 110 can estimate the
number of LTE users within the range of its WiFi network. Once the
number of users for the WiFi network and for the neighboring
network(s) has been estimated, the communication processor 110
obtains the statistics of its own successful channel access (e.g.,
based on a rolling time window a previous channel accesses), and
compares it to a baseline/threshold probability of success for
communication and/or a communication probability for a particular
UE 103.
[0027] Generally, the baseline probability of successful channel
access is a theoretical probability computed for multiple networks
of the same type. For example, graph 230 of FIG. 3 illustrates when
an LTE network is present within the range of a WiFi Network. The
curve 231 shows the case when two WiFi networks coexist with each
other. In this embodiment, the curve 231 is used as a baseline that
WiFi networks coexist fairly well with each other (e.g., by sharing
resources equally). The probability of successful channel access is
a function of the number of users associated with the WiFi network
(e.g., WAP 104) and the number of users associated with another
network within range of the WiFi network
[0028] The baseline curve 231 can be computed for a variety of
cases, including multiple networks in the vicinity of the WAP 104
and/or multiple UEs 103 in each network. The baseline 231 may be
computed offline by the communication processor 110, stored in a
database, and pushed to the WAP 104 to reduce the computation
burden on the WAP 104.
[0029] To illustrate, an LAA-LTE network is present within the
range of the WiFi Network as shown in FIG. 3. A data point on the
curve 232 represents actual statistics collected by a WiFi network
WAP. The communication processor 110 compares the collected data
point to the corresponding baseline on the curve 231 for the same
number of UEs 103, and determines that the actual successful
channel access rate is significantly lower than the baseline.
Accordingly, the WAP 104/communication processor 110 of a WiFi
Network embodiment determines that the LAA network is behaving
aggressively.
[0030] The graph 240 of FIG. 4 illustrates baseline collision
probability that can be used by the network WAP. For example,
instead of or in addition to determining the probability of
successful transmission, the WAP 104/communication processor 110
can determine the probability of a collision when encountering
aggressive activity by another network (e.g., the RAN 102). The
baseline curve 241 illustrates when how communications collisions
with others can be overcome through standard communications. For
example, for data points under the curve 241, collision probability
is relatively low meaning there is no need to change communication
strategies. However, data points above the curve 241 mean that
collisions are likely to occur and that another network is behaving
aggressively. So, the WAP 104 may need to change its communication
strategy, as discussed below.
[0031] Once the communication processor 110 determines that the
other network is behaving aggressively, the communication processor
110 can identify ways to overcome the aggressive activity of the
other network. FIG. 5 is a block diagram of a WiFi communication
system operable when encountering aggressive behavior from an LTE
communication system. In this embodiment, the WAP 104 is a WiFi WAP
and the RAN point 102 is an LTE RAN point. However, the invention
is not intended to be limited simply to WiFi and LTE as other
communication technologies may be used. For example, the inventive
aspects herein may be used in any communication systems that do not
have contention mechanisms built in when encountering different
communication technologies.
[0032] Existing implementations of WiFi networks follow the
contention-based DCF and EDCA MAC protocols when contending with
other WiFi networks for RF resources. However, WiFi networks may
reserve the medium for the WiFi WAP 104 to override the regular
DCF/EDCA back off mechanisms. For example, in response to other
aggressive users of unlicensed spectrum, the communication
processor 110 may override the backoff mechanisms such that the
WiFi WAP 104 remains in "LISTEN" mode if other WiFi WAPs follow the
regular 802.11 back off rules. Alternatively or additionally, CSMA
(Carrier sense multiple access) contention-based medium access
becomes inefficient and channel utilization degrades when a large
number of WiFi WAPs contend for a channel due to a high number of
collisions. Accordingly, WiFi WAPs can employ a schedule-based
access to the medium, which improves the channel utilization.
[0033] Without changing the baseline DCF/EDCA MAC protocol
implementation, the communication processor 110 can enable the WiFi
WAP 104 to access the medium according to a schedule and in a
contention-free manner. For example, default access to the medium
by WiFi WAPs will remain contention-based. When the WiFi WAP 104
perceives that contention-free access to the medium is necessary
(e.g., when aggressive behavior from other users of the unlicensed
spectrum is detected or when the level of contention is so high
that it leads to poor channel utilization if WAPs follow the
regular contention-based medium access rules), the WAP triggers the
UEs 103.
[0034] Consider the WiFi network 105 with one WiFi WAP 104 and "N"
UEs 103 associated with the WAP 104. The WiFi WAP 104 "knows" the
identity of its associated UEs 103 through their MAC addresses. The
WiFi WAP 104 determines that it needs to grant its associated UEs
103 (or some subset of them, "M", wherein "M" is also an integer
greater than 1 and not necessarily equal to any other "M" reference
herein) access the medium in a contention-free manner. This group
is denoted as the "contention-free group". The WAP 104 may perceive
interference from aggressive interference sources on the "M" UEs
103. Accordingly, the WAP 104 may perceive a high level of
contention and low channel utilization as measured through the
collision rate.
[0035] The WAP 104 may send a "trigger frame", which is a short
payload-free packet containing PHY and MAC layer headers destined
to the "M" number of UEs 103 of the contention-free group one at a
time as illustrated in FIG. 6. The WAP 104 may set one of the
currently unused bits in the MAC header to indicate to all of its
"N" associated UEs 103 that the UE 103 whose MAC address matches
the RA (receiver address) field of the MAC header is allowed to
over-ride the regular channel sensing and back off mechanism to
transmit its packet immediately. In doing so, the WAP 104 may set
the length field in the MAC header of the trigger frame equal to a
predefined value.
[0036] The other "N-1" clients (i.e., whose MAC address do not
match) will set their network allocation vectors (NAVs) and freeze
their back off timers accordingly. Examples of the unused bits in
the MPDU (media access control protocol data unit) header that can
be used are in the HT capabilities field. For example, the HT
capabilities of the MAC provides modulation and coding scheme (MCS)
values which are supported by the WiFi WAP 104. These data rates
can be used by both the WAP 104 and a UE 103 to send unicast
traffic back and forth. However, some of these bits are unused in
the 802.11n HT capabilities field and can be used to indicate to
the UE 103 to switch to contention free access. Alternatively or
additionally, a reserved bit in the HT capabilities field of
802.11ac can be used. Examples of these are illustrated in FIGS. 7
and 8.
[0037] FIG. 7 illustrates the 802.11n HT capabilities field 350
having unused bits 351 and 352 being capable of employing the
messaging used to direct the UEs 103 to employ contention free
access. FIG. 8 illustrates the 802.11ac HT capabilities field 360
with the reserved bit 361 being capable of employing the messaging
used to direct the UEs 103 to employ contention free access.
[0038] Each of the "M" clients in the contention-free group, upon
receiving the opportunity to transmit, looks at the packets in its
queue and sends a frame whose length plus the ACK (acknowledgment)
from the WAP 104 is less than the predefined length value. If the
length of all of the available packets is more than this predefined
value, then the UE 103 will send an ACK indicating to the WAP 104
that it cannot use this transmission opportunity. The WAP 104 may
then provide multiple transmission opportunities for a particular
UE 103 by sending multiple trigger frames with the UE 103's MAC
address in the RA field of MPDU.
[0039] With these above embodiments in mind, the communication
processor 110 and the WAP 104 are operable to implement a process
that directs the UEs 103 to operate in a contention free mode. FIG.
9 is a flowchart illustrating an exemplary process 300 of the
communication system of FIG. 5. In this embodiment, the WAP 104
establishes a link between a first UE 103 (UE 103-1) in a typical
DCF mode, in the process element 301. This allows the UEs 103 to
contend for access to the WiFi network 105 through the WAP 104 as
is normally done.
[0040] The WAP 104 may then query the first UE 103 (e.g., UE 103-1)
to determine whether any aggressive RF band activity by another
communication system is within range of the WAP 104, in the process
element 302. For example, the UE 103 and others like it may be able
to operate using WiFi and LTE communications. If an LTE
communication system is operating within range of the WAP 104, the
WAP 104 may begin to experience high collision rates and/or low
successful transmission rates with the UE 103. Accordingly, the WAP
104 may direct the UE 103 to contact neighboring UEs 103 to
determine how many UEs 103 are operating with the LTE communication
system.
[0041] When a UE 103 is operating with an LTE network, the LTE RAN
102 reserves spectrum for each of its UEs. Accordingly, each of the
UEs 103 communicating with the LTE RAN 102 may know its precise
channel under which is communicating. In this regard, the WiFi WAP
104 can transmit a message to the UEs 103 (e.g., the one of the
unused bits in the MAC headers) that directs the UEs 103 to report
the frequencies which they are occupying. Then, based on the number
of UEs 103 reporting back to the WAP 104, the communication
processor 110 can compare the estimated communication success rate
and/or the collision rate to the baseline level as mentioned above,
in the process element 303, so as to determine whether the success
rate is below a particular threshold level and/or whether the
collision rate is above a particular threshold level, in the
process element 304.
[0042] If the communication success rate is below the threshold
level, then the WAP 104 directs its client UEs 103 to switch to the
contention free mode, in the process element 305. This ensures that
the UEs communicate with the WAP 104 in a contention free mode.
That is, the UEs 103 are directed to operate without regard to
other networks in the area, in essence becoming as aggressive as
the LTE RAN 102. Otherwise, the WAP 104 continues to query the UEs
103 within range of the WAP 104 to essentially monitor the activity
of any potential LTE networks. Similarly, after the WAP 104 directs
the UE 103 to switch to the contention free mode, the WAP 104
continues to monitor the aggressive activity of the LTE networks,
in the process element 302, to switch the UE to the contention
based mode once the activity ceases, thereby allowing the WAP 104
to coexist with other WiFi WAPs in the vicinity.
[0043] Alternatively or additionally, the UEs 103, when attempting
to connect to the WAP 104, may automatically transfer an indicator
that the UEs 103 also have LTE capabilities. For example, an
acknowledgment frame to the WiFi WAP 104, a UE 103 may indicate in
an unused bit of a header to show that the UE 103 has the LTE
capability. The WAP 104 detects this indicator and determines if
the UE 103 is communicating with the LTE network. If so, then the
WAP 104 issues a new control frame to the UE 103 that directs the
UE 103 to turn the CSMA capability of the UE 103 off. This new WiFi
control frame may include the existing PHY and MAC header per WiFi
spec as well as a one bit indicator that controls the CSMA
capability of the UE 103.
[0044] The invention can take the form of an entirely hardware
embodiment, an entirely software embodiment or an embodiment
containing both hardware and software elements. In one embodiment,
the invention is implemented in software, which includes but is not
limited to firmware, resident software, microcode, etc. FIG. 6
illustrates a computing system 400 in which a computer readable
medium 406 may provide instructions for performing any of the
methods disclosed herein.
[0045] Furthermore, the invention can take the form of a computer
program product accessible from the computer readable medium 406
providing program code for use by or in connection with a computer
or any instruction execution system. For the purposes of this
description, the computer readable medium 406 can be any apparatus
that can tangibly store the program for use by or in connection
with the instruction execution system, apparatus, or device,
including the computer system 400.
[0046] The medium 406 can be any tangible electronic, magnetic,
optical, electromagnetic, infrared, or semiconductor system (or
apparatus or device). Examples of a computer readable medium 406
include a semiconductor or solid state memory, magnetic tape, a
removable computer diskette, a random access memory (RAM), a
read-only memory (ROM), a rigid magnetic disk and an optical disk.
Some examples of optical disks include compact disk--read only
memory (CD-ROM), compact disk--read/write (CD-R/W) and DVD.
[0047] The computing system 400, suitable for storing and/or
executing program code, can include one or more processors 402
coupled directly or indirectly to memory 408 through a system bus
410. The memory 408 can include local memory employed during actual
execution of the program code, bulk storage, and cache memories
which provide temporary storage of at least some program code in
order to reduce the number of times code is retrieved from bulk
storage during execution. Input/output (I/O) devices 404 (including
but not limited to keyboards, displays, pointing devices, etc.) can
be coupled to the system either directly or through intervening I/O
controllers. Network adapters may also be coupled to the system to
enable the computing system 400 to become coupled to other data
processing systems, such as through host systems interfaces 412, or
remote printers or storage devices through intervening private or
public networks. Modems, cable modem and Ethernet cards are just a
few of the currently available types of network adapters.
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