WLAN capacity enhancement using SDM
First Claim
Patent Images
1. A method for communication over a wireless local area network (WLAN), comprising:
- receiving uplink signals from a plurality of stations in the WLAN;
responsively to the uplink signals, selecting a set of the stations for inclusion in a spatial multiplexing group; and
transmitting downlink signals simultaneously to the stations in the set using spatial division multiplexing (SDM).
4 Assignments
0 Petitions
Accused Products
Abstract
A method for communication over a wireless local area network (WLAN) includes receiving uplink signals from a plurality of stations in the WLAN. Responsively to the uplink signals, a set of the stations is selected for inclusion in a spatial multiplexing group. Downlink signals are transmitted simultaneously to the stations in the set using spatial division multiplexing (SDM).
-
Citations
156 Claims
-
1. A method for communication over a wireless local area network (WLAN), comprising:
-
receiving uplink signals from a plurality of stations in the WLAN;
responsively to the uplink signals, selecting a set of the stations for inclusion in a spatial multiplexing group; and
transmitting downlink signals simultaneously to the stations in the set using spatial division multiplexing (SDM). - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24)
-
-
25. A method for communication over a wireless local area network (WLAN), comprising:
-
receiving first signals from a plurality of stations in the WLAN;
responsively to the first signals, determining respective spatial signatures of the stations;
calculating beamforming weights based on the spatial signatures; and
communicating with two or more of the stations simultaneously by spatial division multiplexing (SDM) using the beamforming weights. - View Dependent Claims (26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45)
-
-
46. A method for communication over a wireless local area network (WLAN), comprising:
-
selecting a set of stations in the WLAN for inclusion in a spatial multiplexing group;
during a first operating period, permitting the stations in the WLAN to transmit uplink signals subject to a collision-avoidance mechanism provided by a standard applicable to the WLAN;
transmitting a broadcast message from an access point to the stations in the WLAN so as to disable transmission of the uplink signals, thereby terminating the first operating period; and
during a second operating period immediately following the broadcast message, transmitting downlink signals from the access point simultaneously to the stations in the spatial multiplexing group using spatial division multiplexing (SDM). - View Dependent Claims (47, 48, 49, 50, 51, 52)
-
-
53. A method for communication over a wireless local area network (WLAN), comprising:
-
receiving uplink signals at an access point from at least one station in the WLAN via multiple antennas that are coupled to the access point;
finding respective correlations between respective sequences of samples of the uplink signals received by the antennas and a known preamble of a packet carried by the uplink signals;
tracking respective phases of the uplink signals received by the antennas;
combining the respective correlations from the plurality of the antennas so as to recover a timing of the uplink signals; and
combining the respective phases from the plurality of the antennas so as to recover a carrier frequency offset and a carrier phase of the uplink signals. - View Dependent Claims (54, 55, 56, 57, 58)
-
-
59. A method for communication over a wireless local area network (WLAN), comprising:
-
selecting a number of stations in the WLAN for inclusion in a spatial multiplexing group;
determining a downlink transmission rate for the spatial multiplexing group responsively to the number of the stations in the group; and
transmitting downlink signals simultaneously to the stations in the spatial multiplexing group using spatial division multiplexing (SDM) at the downlink transmission rate. - View Dependent Claims (60, 61, 62, 63)
-
-
64. A method for communication over a wireless local area network (WLAN), comprising:
-
providing an access point comprising a plurality of transceivers coupled to respective antennas for communication over the WLAN, the plurality of transceivers comprising at least first and second transceivers, each transceiver comprising a respective transmitter and a respective receiver having respective response characteristics;
configuring the access point to exchange communication signals with a station in the WLAN by communicating simultaneously with the station through the first and second transceivers;
making a measurement of the response characteristics of at least one of the first and second transceivers by transmitting a calibration signal through the transmitter of the first transceiver and receiving the transmitted calibration signal through the receiver of the second transceiver; and
applying calibration factors to the communication signals responsively to the measurement so as to compensate for one or more imperfections in the response characteristics. - View Dependent Claims (65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75)
-
-
76. A method for communication over a wireless local area network (WLAN), comprising:
-
providing an access point comprising a plurality of transceivers coupled to respective antennas for communication over the WLAN, each transceiver comprising;
a respective receiver, which is coupled to receive uplink radio frequency (RF) signals from a station in the WLAN;
a down-converter, which is adapted to down-convert the RF signals to baseband signals having a phase; and
a local oscillator, which is coupled to drive the down-converter, thereby determining the phase of the baseband signals;
configuring the access point to exchange communication signals with a station in the WLAN by communicating simultaneously with the station through the plurality of the transceivers; and
applying a reference signal to the transceivers so as to synchronize the phase of the baseband signals provided by the plurality of transceivers to a digital processing circuit in the access point. - View Dependent Claims (77, 78)
-
-
79. An access point for communication over a wireless local area network (WLAN), comprising:
-
a plurality of transceivers, which are coupled to receive uplink signals via respective antennas from stations in the WLAN;
control circuitry, which is adapted, responsively to the uplink signals, to select a set of the stations for inclusion in a spatial multiplexing group; and
spatial division multiplexing (SDM) circuitry, which is coupled to the transceivers so as to transmit downlink signals simultaneously to the set of the stations in the spatial multiplexing group. - View Dependent Claims (80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102)
-
-
103. An access point for communication over a wireless local area network (WLAN), comprising:
-
a plurality of transceivers, which are coupled to receive first signals via respective antennas from stations in the WLAN;
control circuitry, which is adapted, responsively to the first signals, to determine respective spatial signatures of the stations and to calculate beamforming weights based on the spatial signatures; and
spatial division multiplexing (SDM) circuitry, which is coupled to the transceivers so as to communicate with two or more of the stations simultaneously by spatial division multiplexing (SDM) using the beamforming weights. - View Dependent Claims (104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123)
-
-
124. An access point for communication over a wireless local area network (WLAN), comprising:
-
a plurality of transceivers, which are coupled via respective antennas to communicate with stations in the WLAN;
spatial division multiplexing (SDM) circuitry, which is coupled to the transceivers so as to communicate with a set of the stations simultaneously by spatial division multiplexing (SDM); and
control circuitry, which is configured to permit the stations in the WLAN to transmit uplink signals during a first operating period, subject to a collision-avoidance mechanism provided by a standard applicable to the WLAN, and to transmit a broadcast message to the stations so as to disable transmission of the uplink signals, thereby terminating the first operating period, and to cause the SDM circuitry to transmit downlink signals simultaneously to the stations in the set during a second operating period immediately following the broadcast message. - View Dependent Claims (125, 126, 127, 128, 129, 130)
-
-
131. An access point for communication over a wireless local area network (WLAN), comprising:
-
a plurality of transceivers, which are coupled via respective antennas to receive uplink signals from at least one station in the WLAN; and
control circuitry, which is adapted to find respective correlations between respective sequences of samples of the uplink signals received by the antennas and a known preamble of a packet carried by the uplink signals, and to track respective phases of the uplink signals received by the antennas, and to combine the respective correlations from the plurality of the antennas so as to recover a timing of the uplink signals, and to combine the respective phases from the plurality of the antennas so as to recover a carrier frequency offset and a carrier phase of the uplink signals. - View Dependent Claims (132, 133, 134, 135, 136)
-
-
137. An access point for communication over a wireless local area network (WLAN), comprising:
-
a plurality of transceivers, which are coupled via respective antennas to communicate with stations in the WLAN;
spatial division multiplexing (SDM) circuitry, which is coupled to the transceivers so as to communicate with a number of the stations in a spatial multiplexing group simultaneously by spatial division multiplexing (SDM); and
control circuitry, which is adapted to determine a downlink transmission rate for the spatial multiplexing group responsively to the number of the stations in the group, and to cause the SDM circuitry to transmit downlink signals simultaneously to the stations in the spatial multiplexing group using SDM at the downlink transmission rate. - View Dependent Claims (138, 139, 140, 141)
-
-
142. An access point for use in a wireless local area network (WLAN), comprising:
-
a plurality of antennas;
a plurality of transceivers, the plurality comprising at least first and second transceivers, each transceiver comprising a respective transmitter and a respective receiver, which are coupled to a respective one of the antennas and have respective response characteristics;
a digital processing circuit, which is coupled to exchange communication signals with a station in the WLAN by communicating simultaneously through the first and second transceivers; and
a calibration circuit, which is coupled to make a measurement of the response characteristics of at least one of the first and second transceivers by transmitting a calibration signal through the transmitter of the first transceiver and receiving the transmitted calibration signal through the receiver of the second transceiver, and which is adapted to determine calibration factors for application to the communication signals responsively to the measurement so as to compensate for one or more imperfections in the response characteristics. - View Dependent Claims (143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 156)
-
-
154. An access point for use in a wireless local area network (WLAN), comprising:
-
a plurality of antennas;
a plurality of transceivers, each comprising;
a respective receiver, which is coupled to receive uplink radio frequency (RF) signals from a station in the WLAN via a respective one of the antennas;
a down-converter, which is adapted to down-convert the RF signals to baseband signals having a phase; and
a local oscillator, which is coupled to drive the down-converter, thereby determining the phase of the baseband signals;
a digital processing circuit, which is coupled to receive and process the baseband signals simultaneously from the plurality of the transceivers; and
a transceiver controller, which is coupled to provide a reference signal to the transceivers so as to synchronize the phase of the baseband signals provided by the plurality of transceivers to the digital processing circuit. - View Dependent Claims (155)
-
Specification