WO2004019539A2 - System and method for medium access control in a wireless network - Google Patents

System and method for medium access control in a wireless network Download PDF

Info

Publication number
WO2004019539A2
WO2004019539A2 PCT/US2003/026633 US0326633W WO2004019539A2 WO 2004019539 A2 WO2004019539 A2 WO 2004019539A2 US 0326633 W US0326633 W US 0326633W WO 2004019539 A2 WO2004019539 A2 WO 2004019539A2
Authority
WO
WIPO (PCT)
Prior art keywords
unit
wireless
smart antenna
area
communication channel
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US2003/026633
Other languages
French (fr)
Other versions
WO2004019539A3 (en
Inventor
Jacob Sharony
Joseph Katz
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Symbol Technologies LLC
Original Assignee
Symbol Technologies LLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Symbol Technologies LLC filed Critical Symbol Technologies LLC
Priority to AU2003265675A priority Critical patent/AU2003265675A1/en
Publication of WO2004019539A2 publication Critical patent/WO2004019539A2/en
Publication of WO2004019539A3 publication Critical patent/WO2004019539A3/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/04—Wireless resource allocation
    • H04W72/044—Wireless resource allocation based on the type of the allocated resource
    • H04W72/046—Wireless resource allocation based on the type of the allocated resource the resource being in the space domain, e.g. beams
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/02—Hierarchically pre-organised networks, e.g. paging networks, cellular networks, WLAN [Wireless Local Area Network] or WLL [Wireless Local Loop]
    • H04W84/10—Small scale networks; Flat hierarchical networks
    • H04W84/12—WLAN [Wireless Local Area Networks]

Definitions

  • SAs smart antennas
  • Deploying the SAs in communication systems has several known benefits, e.g., extended range, higher capacity, interference mitigation, lower power, etc.
  • multiple access wireless networks e.g., IEEE 802.11b wireless standard
  • some form of collision avoidance is required. For example, when there is a directed-beam transmission to a target mobile unit (“MU”), it may not be heard by a neighboring MU. The neighboring M ⁇ then would mistakenly assume that the radio frequency or channel is free and attempt to access it, thereby, causing a collision with an ongoing transmission.
  • MU target mobile unit
  • RTS/CTS Request to Send / Clear to Send
  • the present invention relates to a method and system for access control in a communication network which includes a first wireless unit, a second wireless unit and at least one further unit.
  • the first unit generates a frame for the second unit.
  • the frame includes a first portion and a second portion.
  • the first portion includes data indicating that the first unit is about to establish a direct communication channel with the second unit.
  • the first portion is transmitted to the second unit and is received by the at least one further wireless unit .
  • a direct communication channel is established between the first unit and the second unit for transmission of the second portion.
  • the at least one further unit abstains from communications using the direct communication channel .
  • Figure 1 shows an exemplary embodiment of a wireless network according to the present invention
  • Figure 2 shows an exemplary method according to the present invention
  • Figure 3 shows an exemplary embodiment of a frame.
  • the present invention relates to a method and system for medium access control ("MAC”) in a wireless communication network that employs smart antennas (“SAs”) .
  • SAs smart antennas
  • MAC medium access control
  • CSMA- CA Carrier Sense Multiple Access - Collision Avoidance
  • the CSMA-CA protocol requires that before initiating any communications on the wireless network a mobile unit ("MU") or an access point ("AP") must check for any activity on a communication channel .
  • MU mobile unit
  • AP access point
  • the MU or the AP employs the SAs to direct their transmissions, it is possible that other MUs or APs may not detect the transmission and thus may cause interference on the communication channel .
  • the present invention resolves this problem, as described in detail below, by employing a split frame that initially transmits, in an omnidirectional beam pattern, a header portion of the frame for informing other wireless units to abstain from communications using the communication channel. Then, the SA changes to a directed beam focused on the target MU and transmits the data via the communication channel.
  • FIG. 1 shows an exemplary embodiment of a wireless network 1, e.g., a 802.11 wireless network.
  • the wireless network 1 may include a plurality of wireless communication devices (e.g., MUs 20-24) and a plurality of access points (e.g., AP 10). All of the MUs 20-24 may be within the omni-directional coverage area 100 of the AP 10, while the target MU 20 may also be within a directed beam 150 of the SA 15.
  • the MUs 20-24 may be a conventional computing arrangement (e.g., a desktop or laptop computers, PDAs, cell phones, two-way pagers, etc.) which includes a wireless communication arrangement (e.g., a wireless modem, transmitter, etc.) .
  • the AP 10 may be a wireless router or a transceiver box that provides access for the MUs 20-24 to the wireless and wired network 1.
  • the SA 15 combines a specialized array of many small antennas with a digital signal processor ("DSP") .
  • the DSP can determine the optimal beam pattern to transmit and/or receive a signal . Depending on the sophistication of the SA system, the DSP may then switch to the optimal antenna or use the antenna array to actually shape a specific antenna pattern. This may be a directional beam 150 that the SA 15 creates when a payload portion 44 of a frame 40 ( Figure 3) is sent.
  • the SA 15 When the SA 15 transmits data packets in the omni directional coverage area 100, it shapes the beam to cover all directions (i.e., 360 degrees) with an equally powered signal. It is also possible that the maximal or intended coverage area of the AP 10 is not circular, for example, the AP 10 is stationed in the corner of a building or in a valley. In such cases the beam may be adjusted for the geography of a particular network.
  • Figure 2 shows a method according to an exemplary embodiment of the present invention. The method is described with reference to Figures 1 and 3. Other configurations with different numbers of MUs equipped or not equipped with SAs, and APs equipped or not equipped with SAs, may also be used.
  • FIG. 3 shows an exemplary embodiment of a frame 40 used for MAC and data transfers.
  • the frame 40 may include two portions: a header portion 42 and a payload portion 44.
  • the header portion 42 may include data necessary for MAC and be transmitted in the omni-directional coverage area 100 by the SA 15 to a particular MU (e.g., the MU 20) .
  • a particular MU e.g., the MU 20
  • the payload portion 44 may include a plurality of data packets storing data specifically designated for the target MU 20 and is transmitted using the directional beam 150.
  • the MAC process is initiated in step 200 with the AP 10 transmitting the header portion 42.
  • the SA 15 transmits the header portion 42 in the omni-directional coverage area 100 so that the MU 20 may receive it.
  • the header portion 42 is transmitted at a particular rate (e.g., a "common denominator" rate) which is acceptable by most devices of the wireless network 1.
  • the particular data rate may be the lowest data rate supported by the wireless network 1 so that all other MUs may receive the header portion 42.
  • the AP 10 in order for the AP 10 to provide an optimal transmission performance (i.e., balancing throughput and coverage) multiple data rates may be used in the wireless network 1. If the MU 20 is close to the AP 10, a higher data rate and a lower transmission power may be used to most efficiently transmit the data in the shortest amount of time. When the MUs 20-24 are farther from the AP 10, the AP 10 is unable to communicate at the higher data rate and the lower transmission power. In order to provide greater coverage, the AP 10 may communicate at a lower data rate and higher power to assure that all the MUs 20-24 may receive and process the header portion 42.
  • the AP 10 may communicate at a lower data rate and higher power to assure that all the MUs 20-24 may receive and process the header portion 42.
  • the far reaching transmission of the header portion 42 may provide an added benefit. Any MUs not in the wireless network 1, but rather in adjacent wireless networks may also participate in the following steps. This further reduces interference in the transmission of the payload portion 44.
  • the MUs 20-24 receive the header portion 42.
  • the header portion 42 may include data for the MUs 21-24 indicating that the communication channel is being utilized by the AP 10 to communicate with the MU 20.
  • the header portion 42 may also include information such as data rate and packet length or any other information that may be used by the MUs 21-24 to determine the time length of the communication. During this time period the MUs 21-24 refrain from using the communication channel even if they do not detect any activity. Thus, the MUs 21-24 avoid the possibility of colliding with any communications between the AP 10 and the MU 20.
  • step 204 the AP 10 sends the payload portion 44 of the frame 40 to the MU 20.
  • the SA 15 transmits the payload portion 44 using the directional beam 150.
  • the payload portion 44 is delivered within the period of time specified in the header portion 42; otherwise, the payload portion 44 may collide with transmissions from the MUs 21-24 because they do not detect that the communication channel is still in use.
  • step 206 the reservation period specified by the header portion 42 has expired, and normal operations on the communication channel resume. Normal operations may include the MUs 20-24 and the APs 10 using the CSMA-CA MAC in conjunction with the present invention.
  • the system may also use the present invention as the exclusive method of MAC in conjunction with a collision detection and correction scheme.
  • the present invention has been described with reference to an embodiment having five MUs and one AP. However, other embodiments may be devised having additional APs and/or additional or fewer MUs . The AP and one of the MUs may even be interchanged in the MAC process. In addition, those skilled in the art will understand that the present invention may work for both communications between the AP 10 and the MUs 20-24 (i.e., from the AP 10 to a particular MU and from a particular MU to the AP 10) . Accordingly, various modifications and changes may be made to the embodiments without departing from the broadest spirit and scope of the present invention as set forth in the claims that follow. The specification and drawings are accordingly to be regarded in an illustrative rather than restrictive sense.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

Described is a method and system for an access control in a communication network which includes a first wireless unit, a second wireless unit and at least one further unit. The first unit generates a frame for the second unit. The frame includes a first portion and a second portion. The first portion includes data indicating that the first unit is about to establish a direct communication channel with the second unit. The first portion is transmitted to the second unit and is received by the at least one further wireless unit. The direct communication channel is established between the first unit and the second unit for transmission the second portion. During the transmission of the second portion, the at least one further unit abstains from communications using the direct communication channel.

Description

System and Method for Medium Access Control in a Wireless Network
Background of the Invention
[0001] The proliferation of conventional wireless and computing devices in the recent past has been exceptional . These devices are capable of exchanging data and/or voice signals among each other and/or with a central location using radio waves over dedicated frequencies or dedicated segments of the electromagnetic spectrum. The speed and range of these wireless communications is limited by, among other things, interference and power limitations . There is an ongoing effort to overcome these issues and to make these wireless communications as fast as their wired cousins and to increase their effective range.
[0002] One of the ways to overcome the above mentioned issues is by utilizing smart antennas ("SAs"). Deploying the SAs in communication systems has several known benefits, e.g., extended range, higher capacity, interference mitigation, lower power, etc. When using the SAs in conjunction with multiple access wireless networks (e.g., IEEE 802.11b wireless standard) some form of collision avoidance is required. For example, when there is a directed-beam transmission to a target mobile unit ("MU"), it may not be heard by a neighboring MU. The neighboring Mϋ then would mistakenly assume that the radio frequency or channel is free and attempt to access it, thereby, causing a collision with an ongoing transmission. One possible solution for this problem is to use the built-in Request to Send / Clear to Send ("RTS/CTS") mechanism as described in the 802.11 standard. The RTS/CTS mechanism provides for a four-way handshake that results in higher overhead (e.g., two extra portions required to transmit one payload) . There is a need for a system and method to eliminate this overhead without transmitting additional portions.
Summary of the Invention
[0003] The present invention relates to a method and system for access control in a communication network which includes a first wireless unit, a second wireless unit and at least one further unit. The first unit generates a frame for the second unit. The frame includes a first portion and a second portion. The first portion includes data indicating that the first unit is about to establish a direct communication channel with the second unit. The first portion is transmitted to the second unit and is received by the at least one further wireless unit .
[0004] A direct communication channel is established between the first unit and the second unit for transmission of the second portion. During the transmission of the second portion, the at least one further unit abstains from communications using the direct communication channel .
Brief Descrrption of the Drawings
[0005] Figure 1 shows an exemplary embodiment of a wireless network according to the present invention;
Figure 2 shows an exemplary method according to the present invention; and Figure 3 shows an exemplary embodiment of a frame.
Detailed Description
[0006] The present invention relates to a method and system for medium access control ("MAC") in a wireless communication network that employs smart antennas ("SAs") . Generally, it is highly desirable to employ the SA to improve the range and speed of the wireless network. Unfortunately, this comes at the expense of causing problems with the standard MAC protocol known as Carrier Sense Multiple Access - Collision Avoidance ("CSMA- CA") .
[0007] In particular, the CSMA-CA protocol requires that before initiating any communications on the wireless network a mobile unit ("MU") or an access point ("AP") must check for any activity on a communication channel . When the MU or the AP employs the SAs to direct their transmissions, it is possible that other MUs or APs may not detect the transmission and thus may cause interference on the communication channel . The present invention resolves this problem, as described in detail below, by employing a split frame that initially transmits, in an omnidirectional beam pattern, a header portion of the frame for informing other wireless units to abstain from communications using the communication channel. Then, the SA changes to a directed beam focused on the target MU and transmits the data via the communication channel.
[0008] Figure 1 shows an exemplary embodiment of a wireless network 1, e.g., a 802.11 wireless network. The wireless network 1 may include a plurality of wireless communication devices (e.g., MUs 20-24) and a plurality of access points (e.g., AP 10). All of the MUs 20-24 may be within the omni-directional coverage area 100 of the AP 10, while the target MU 20 may also be within a directed beam 150 of the SA 15.
[0009] The MUs 20-24 may be a conventional computing arrangement (e.g., a desktop or laptop computers, PDAs, cell phones, two-way pagers, etc.) which includes a wireless communication arrangement (e.g., a wireless modem, transmitter, etc.) . The AP 10 may be a wireless router or a transceiver box that provides access for the MUs 20-24 to the wireless and wired network 1. The SA 15 combines a specialized array of many small antennas with a digital signal processor ("DSP") . The DSP can determine the optimal beam pattern to transmit and/or receive a signal . Depending on the sophistication of the SA system, the DSP may then switch to the optimal antenna or use the antenna array to actually shape a specific antenna pattern. This may be a directional beam 150 that the SA 15 creates when a payload portion 44 of a frame 40 (Figure 3) is sent.
[0010] When the SA 15 transmits data packets in the omni directional coverage area 100, it shapes the beam to cover all directions (i.e., 360 degrees) with an equally powered signal. It is also possible that the maximal or intended coverage area of the AP 10 is not circular, for example, the AP 10 is stationed in the corner of a building or in a valley. In such cases the beam may be adjusted for the geography of a particular network.
[0011] Figure 2 shows a method according to an exemplary embodiment of the present invention. The method is described with reference to Figures 1 and 3. Other configurations with different numbers of MUs equipped or not equipped with SAs, and APs equipped or not equipped with SAs, may also be used.
[0012] Figure 3 shows an exemplary embodiment of a frame 40 used for MAC and data transfers. The frame 40 may include two portions: a header portion 42 and a payload portion 44. The header portion 42 may include data necessary for MAC and be transmitted in the omni-directional coverage area 100 by the SA 15 to a particular MU (e.g., the MU 20) . Although the header portion 42 is transmitted to the MU 20, other MUs 21-24 may "hear" the header portion 42. The payload portion 44 may include a plurality of data packets storing data specifically designated for the target MU 20 and is transmitted using the directional beam 150.
[0013] The MAC process is initiated in step 200 with the AP 10 transmitting the header portion 42. The SA 15 transmits the header portion 42 in the omni-directional coverage area 100 so that the MU 20 may receive it. The header portion 42 is transmitted at a particular rate (e.g., a "common denominator" rate) which is acceptable by most devices of the wireless network 1. The particular data rate may be the lowest data rate supported by the wireless network 1 so that all other MUs may receive the header portion 42.
[0014] For example, in order for the AP 10 to provide an optimal transmission performance (i.e., balancing throughput and coverage) multiple data rates may be used in the wireless network 1. If the MU 20 is close to the AP 10, a higher data rate and a lower transmission power may be used to most efficiently transmit the data in the shortest amount of time. When the MUs 20-24 are farther from the AP 10, the AP 10 is unable to communicate at the higher data rate and the lower transmission power. In order to provide greater coverage, the AP 10 may communicate at a lower data rate and higher power to assure that all the MUs 20-24 may receive and process the header portion 42.
[0015] The far reaching transmission of the header portion 42 may provide an added benefit. Any MUs not in the wireless network 1, but rather in adjacent wireless networks may also participate in the following steps. This further reduces interference in the transmission of the payload portion 44.
[0016] In step 202, the MUs 20-24 receive the header portion 42. The header portion 42 may include data for the MUs 21-24 indicating that the communication channel is being utilized by the AP 10 to communicate with the MU 20. The header portion 42 may also include information such as data rate and packet length or any other information that may be used by the MUs 21-24 to determine the time length of the communication. During this time period the MUs 21-24 refrain from using the communication channel even if they do not detect any activity. Thus, the MUs 21-24 avoid the possibility of colliding with any communications between the AP 10 and the MU 20.
[0017] In step 204, the AP 10 sends the payload portion 44 of the frame 40 to the MU 20. The SA 15 transmits the payload portion 44 using the directional beam 150. The payload portion 44 is delivered within the period of time specified in the header portion 42; otherwise, the payload portion 44 may collide with transmissions from the MUs 21-24 because they do not detect that the communication channel is still in use.
[0018] In step 206, the reservation period specified by the header portion 42 has expired, and normal operations on the communication channel resume. Normal operations may include the MUs 20-24 and the APs 10 using the CSMA-CA MAC in conjunction with the present invention. The system may also use the present invention as the exclusive method of MAC in conjunction with a collision detection and correction scheme.
[0019] The present invention has been described with reference to an embodiment having five MUs and one AP. However, other embodiments may be devised having additional APs and/or additional or fewer MUs . The AP and one of the MUs may even be interchanged in the MAC process. In addition, those skilled in the art will understand that the present invention may work for both communications between the AP 10 and the MUs 20-24 (i.e., from the AP 10 to a particular MU and from a particular MU to the AP 10) . Accordingly, various modifications and changes may be made to the embodiments without departing from the broadest spirit and scope of the present invention as set forth in the claims that follow. The specification and drawings are accordingly to be regarded in an illustrative rather than restrictive sense.

Claims

What is claimed is:
1. A method for an access control in a communication network including a first wireless unit, a second wireless unit and at least one further unit, the method comprising the steps of: generating, by the first unit, a frame for the second unit, the frame including a first portion and a second portion, the first portion including data indicating that the first unit is establishing a direct communication channel with the second unit; transmitting the first portion to the second unit, the first portion being received by the at least one further wireless unit; and establishing the direct communication channel between the first unit and the second unit to transmit the second portion, wherein during transmission of the second portion, the at least one further unit abstains from communications using the direct communication channel.
2. The method according to claim 1, wherein the first unit is a wireless access point having a smart antenna, the second unit and the at least one further units being wireless mobile units.
3. The method according to claim 2 , wherein the access point and the mobile units communicate using an 802.11 communication protocol .
4. The method according to claim 1, wherein the first unit and the at least one further units are wireless mobile units, the second unit being a wireless access point, the first having a smart antenna.
5. The method according to claim 1, wherein the first unit transmits the first portion over a first area covering the entire communication network.
6. The method according to claim 5, wherein the first unit includes a smart antenna, the second portion being transmitted, using the smart antenna, within a second area of the first area, the second area being an area covered by the smart antenna .
7. The method according to claim 6, wherein the first portion is transmitted at a first transmission rate and the second portion is transmitted at a second transmission rate, the second transmission rate being higher than the first transmission rate.
8. The method according to claim 7, wherein the first rate is a rate at which the second unit and the at least one further unit are capable of receiving the first portion.
9. The method according to claim 1, wherein the first portion includes data indicative of a particular time period for transmitting the second portion, the at least one further unit abstains from utilizing the directional channel during the particular time period.
10. The method according to claim 1, further comprising the step of: resuming utilization of the direct channel by the at least one further unit after transmission of the second portion.
11. A system, comprising: a first wireless unit; a second wireless unit; and at least one further unit, wherein the first unit generates a frame for the second unit, the frame including a first portion and a second portion, the first portion including data indicating that the first unit is about to establish a direct communication channel with the second unit, wherein the first unit transmits the first portion to the second unit, the first portion being received by the at least one further unit, wherein the first and second units establish the direct communication channel to transmit the second portion, wherein during transmission of the second portion, the at least one further unit abstains from communications using the direct communication channel .
12. The system according to claim 11, wherein the first unit is a wireless access point having a smart antenna, the second unit and the at least one further units being wireless mobile units .
13. The system according to claim 12, wherein the access point and the mobile units communicating using an 802.11 communication protocol .
14. The system according to claim 11, wherein the first unit and the at least one further unit are wireless mobile units, the second unit being a wireless access point, the first unit having a smart antenna.
15. The system according to claim 11, wherein the first unit transmits the first portion to a first area covering the entire communication network.
16. The system according to claim 13, wherein the first unit includes a' smart antenna, the second portion being transmitted, using the smart antenna, within a second area of the first area, the second area being an area covered by the smart antenna.
17. The system according to claim 14, wherein the first portion is transmitted at a first transmission rate and the second portion is transmitted at a second transmission rate, the second transmission rate being higher then the first transmission rate.
18. The -system according to claim 15, wherein the first rate is a rate at which the second unit and the at least one further unit are capable of receiving the first portion.
19. The system according to claim 11, wherein the first portion includes data indicative of a particular time period for transmitting the second portion, the at least one further unit abstains from utilization the directional channel during the particular time period.
20. The system according to claim 11, wherein the at least one further unit resumes utilization of the direct channel by after transmission of the second portion.
PCT/US2003/026633 2002-08-26 2003-08-25 System and method for medium access control in a wireless network Ceased WO2004019539A2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2003265675A AU2003265675A1 (en) 2002-08-26 2003-08-25 System and method for medium access control in a wireless network

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US10/227,683 2002-08-26
US10/227,683 US6735445B2 (en) 2002-08-26 2002-08-26 System and method for medium access control in a wireless network

Publications (2)

Publication Number Publication Date
WO2004019539A2 true WO2004019539A2 (en) 2004-03-04
WO2004019539A3 WO2004019539A3 (en) 2004-04-22

Family

ID=31887514

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2003/026633 Ceased WO2004019539A2 (en) 2002-08-26 2003-08-25 System and method for medium access control in a wireless network

Country Status (4)

Country Link
US (2) US6735445B2 (en)
AU (1) AU2003265675A1 (en)
TW (1) TWI328978B (en)
WO (1) WO2004019539A2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009151291A3 (en) * 2008-06-11 2012-01-05 Lg Electronics Inc. Apparatus and method for transmitting and receiving data
US8605634B2 (en) 2008-06-11 2013-12-10 Lg Electronics Inc. Apparatus for controlling power of wireless device and method thereof

Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7099698B2 (en) * 2002-11-04 2006-08-29 Vivato, Inc. Complementary beamforming methods and apparatuses
KR101002883B1 (en) * 2003-10-27 2010-12-21 재단법인서울대학교산학협력재단 Apparatus and Method for Transmitting Power in Wireless Communication System
US20050165946A1 (en) * 2003-12-22 2005-07-28 Intel Corporation Bi-directional wireless LAN channel access
DE602004012458T2 (en) * 2004-06-08 2009-04-23 Telefonaktiebolaget Lm Ericsson (Publ) FLEXIBLE FEEBACK CALCULATION MECHANISMS FOR IP MULTIMEDIA SERVICES
US7697958B2 (en) * 2004-08-16 2010-04-13 Farrokh Mohamadi Wireless repeater
US8504110B2 (en) * 2004-09-10 2013-08-06 Interdigital Technology Corporation Method and apparatus for transferring smart antenna capability information
US20060056345A1 (en) * 2004-09-10 2006-03-16 Interdigital Technology Corporation Method and system for supporting use of a smart antenna in a wireless local area network
EP3576310B1 (en) * 2004-09-10 2023-03-22 InterDigital Technology Corporation Implementing a smart antenna in a wireless local area network
US7382758B2 (en) * 2004-11-30 2008-06-03 Motorola, Inc. Medium access control for simultaneous channel communications
US8570938B2 (en) * 2008-08-29 2013-10-29 Empire Technology, Development, LLC Method and system for adaptive antenna array pairing
US8577296B2 (en) 2008-08-29 2013-11-05 Empire Technology Development, Llc Weighting factor adjustment in adaptive antenna arrays
US8126486B2 (en) * 2008-08-29 2012-02-28 Empire Technology Development Llc Adaptive antenna weighting system for wireless local area and personal area networks
US8310947B2 (en) * 2009-06-24 2012-11-13 Empire Technology Development Llc Wireless network access using an adaptive antenna array
JP6288268B2 (en) * 2014-06-09 2018-03-07 株式会社村田製作所 Wireless communication device, wireless communication method, and computer program
US9872298B2 (en) * 2015-04-16 2018-01-16 Qualcomm Incorporated System and method for reducing collisions in wireless networks
EP3751947B1 (en) * 2018-02-14 2025-02-12 Guangdong Oppo Mobile Telecommunications Corp., Ltd. Signal transmission method and device

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2444432C (en) * 2001-04-18 2011-02-08 Skypilot Network, Inc. Wireless mesh network and network node
US7075902B2 (en) * 2002-02-11 2006-07-11 Hrl Laboratories, Llc Apparatus, method, and computer program product for wireless networking using directional signaling
US7630403B2 (en) * 2002-03-08 2009-12-08 Texas Instruments Incorporated MAC aggregation frame with MSDU and fragment of MSDU

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009151291A3 (en) * 2008-06-11 2012-01-05 Lg Electronics Inc. Apparatus and method for transmitting and receiving data
US8605634B2 (en) 2008-06-11 2013-12-10 Lg Electronics Inc. Apparatus for controlling power of wireless device and method thereof

Also Published As

Publication number Publication date
US20040157604A1 (en) 2004-08-12
TW200423752A (en) 2004-11-01
AU2003265675A1 (en) 2004-03-11
US20040038695A1 (en) 2004-02-26
WO2004019539A3 (en) 2004-04-22
TWI328978B (en) 2010-08-11
US6735445B2 (en) 2004-05-11
AU2003265675A8 (en) 2004-03-11

Similar Documents

Publication Publication Date Title
US6735445B2 (en) System and method for medium access control in a wireless network
Dai et al. An overview of using directional antennas in wireless networks
US7826431B2 (en) Method of selectively adjusting the configuration of an access point antenna to enhance mobile station coverage
US8160664B1 (en) Omni-directional antenna supporting simultaneous transmission and reception of multiple radios with narrow frequency separation
US6788658B1 (en) Wireless communication system architecture having split MAC layer
CN107197484B (en) Method and apparatus for reliable direct link access
Gossain et al. The deafness problems and solutions in wireless ad hoc networks using directional antennas
Jakllari et al. Handling asymmetry in gain in directional antenna equipped ad hoc networks
Dai et al. An overview of MAC protocols with directional antennas in wireless ad hoc networks
Akhtar et al. Directional MAC protocol for IEEE 802.11 ad based wireless local area networks
CN105706515A (en) Receiver channel reservation
EP1695588B1 (en) Method of communication in a wireless communication network, corresponding station and network
US20050096091A1 (en) Method and system for wireless communications using multiple frequency band capabilities of wireless devices
Arora et al. Power-controlled medium access for ad hoc networks with directional antennas
KR102052233B1 (en) Method for optimizing a wireless network connection
JP2002057677A (en) Wireless packet transmission method
Chen et al. An adaptive MAC protocol for wireless ad hoc networks using smart antenna system
Mahmud et al. Two-dimensional cooperation-based asynchronous multichannel directional MAC protocol for wireless networks
Ullah et al. Optimization of wireless ad-hoc networks using an adjacent collaborative directional MAC (ACDM) protocol
Hsu et al. Performance analysis of directional random access scheme for multiple access mobile ad-hoc wireless networks
US8774140B2 (en) Method and apparatus to provide hidden node protection
Wang et al. Coop-DMAC: A Cooperative Directional MAC protocol for wireless networks
JP2004235839A (en) Fixed wireless access system
Peng et al. DCSR: Directional CSMA/CA-based MAC Protocol with Spatial Reuse for 60GHz mmWave WLANs
Budhwani et al. A MAC layer protocol for sensor networks using directional antennas

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A2

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SY TJ TM TN TR TT TZ UA UG UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A2

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LU MC NL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP

WWW Wipo information: withdrawn in national office

Country of ref document: JP