Cisco Technology, Inc.

Navini Networks, Inc.

Motorola Mobility LLC

Cwill Telecommunications, Inc.

Weidong Yang

Guanghan Xu

Hang Jin

Daniel Wee

Hang Li

John Grabner

Brian L Kurtz

Fan Wang

Philip B Davis

Phil Davis

In an Orthogonal Frequency Division Multiplexing communication system, a radio access network allocates a transmit power for a downlink transmission to a mobile station based on a mean channel quality metric and a channel quality metric second order statistic, in various embodiments a channel quality metric variance or standard deviation, reported by the mobile station.

Method and apparatus for allocating downlink power in an orthogonal frequency division multiplexing communication system

A method and system for interference reduction for telecommunication systems are disclosed. The system comprises a base station control device (BCD) for configuring one or more parameters for operating one or more base stations (BSs), a first BS covering a first cell having one or more mobile terminals therein, a second BS covering a second cell neighboring to the first cell and sharing a predetermined frequency band with the first cell, wherein one or more radio frames constructed for communications between the first BS and any mobile terminal of the first cell and one or more radio frames constructed for communications between the second BS and any mobile terminal of the second cell are distinguishable by defining different channel configuration sets having one or more operation parameters, wherein the parameters includes a training sequence, a spreading code, and a channel observation window position.

Method and system for interference reduction

A system and method for managing control information in a wireless communications system. The method comprises broadcasting a predetermined number of preambles through beamforming from a base station, detecting, by a subscriber station, a predetermined frame associated with one selected preamble that has the highest power level, and identifying one or more subcarriers for carrying control information through the selected preamble.

Method and system for control channel beamforming

A technique for detecting a physical random access channel (PRACH) signal includes demasking a received signal with a demasking signal. In this case, the demasking removes a PRACH root index component from the received signal. A fast Fourier transform is performed on the demasked received signal to provide a time-domain signal. At least three peaks of the time-domain signal from all antennas are then power combined. Finally, a determination is made as to whether a preamble index for the PRACH signal matches a known preamble index based on an output power of the time-domain signal at the at least three peaks.

Techniques for generating and detecting a physical random access channel signal in a wireless communication system

A method and system for reducing interference in a wireless communication network is disclosed. The wireless communication network has at least one base station using an antenna array and one or more code channels to receive or transmit one or more communication signals from or to a plurality of terminals used by one or more users. A signal received by the antenna array carries one or more training sequences and a traffic signal in a frame. After estimating a spatial signature and joint channel response model per user based on the training sequences, one or more spatial weights are found based on the estimated spatial signature and joint channel response model to maximize a signal to noise ratio. A joint detection matrix is then formed based on the estimated spatial weights, the joint channel response model, and a user code channel assignment. After code correlating a traffic signal to obtain one or more user specific multi-antenna signals, a spatial combining is performed on one or more multi-antenna signals associated with each user to generate scalar symbol estimates. Thereafter, a joint detection is done based on the scalar symbol estimates using the joint detection matrix. Similar techniques can be used for downlink communications.

Method and system for interference reduction in a wireless communication network using a joint detector

Techniques are provided herein for generating multiple radiation patterns. An antenna system comprises an antenna array having one or more antennas for providing a first radiation pattern and a second radiation pattern, a transform matrix for transforming one or more inputs into one or more outputs according to a transform function, wherein the outputs of the transform matrix provide signals to the antennas with predetermined phases and magnitudes for generating the first and second radiation patterns, and a transmitter for providing a first set of signals corresponding to the first radiation pattern and a second set of signals corresponding to the second radiation pattern to inputs of the transform matrix.

Method and system for generating multiple radiation patterns using transform matrix

A wireless communication system is disclosed. An available frequency spectrum is divided into multiple channels, a first wireless communication coverage unit is then segregated into a first number of geographical segments. After the segregated channels are grouped into a second number of channel blocks, each channel block is assigned to the segregated geographical segments with predetermined priorities. The above steps are repeated in a fashion that the channels in different channel blocks exhibit no higher mutual interference than the channels in the same channel block, and the channel block assigned for each segregated segment of the first wireless communication coverage unit is different from the channel block assigned for the segregated segment of a second wireless communication coverage unit that immediately borders with the segregated segment of the first wireless coverage unit even if the first and second wireless communication coverage units share the same frequency spectrum.

Method and system for reducing wireless multi-cell interferences through segregated channel assignments and segregated antenna beams

A method and system is disclosed for reducing interference in a wireless communication system utilizing an antenna array. The antenna array uses one or more signal channels for communicating with one or more mobile terminals. First, at least one channel is assigned as an empty channel in which no desired signal is carried so as to provide a representation of all relevant interference. Since the spatial characteristics of the empty channel and the regular signal channels should be very similar, the spatial signature of the signal channels is analyzed based on the interference received on the empty channel and the desired signals received on at least one signal channel. The analyzed spatial signature is then used for reducing the interference on all signal channels.

Method and system for interference assessment and reduction in a wireless communication system

A method and system is disclosed for reducing multi-frequency signal interference in a wireless communication network. An available frequency spectrum is divided into a plurality of channels, a first wireless communication coverage unit is then segregated into a first number of geographical segments. After the segregated channels are grouped into a second number of channel blocks, each channel block is assigned to at least one of the segregated geographical segments with predetermined priorities. All the above steps are repeated for each neighboring wireless communication coverage unit of the first wireless communication coverage unit, wherein the channels in different channel blocks exhibit no higher mutual interference than the channels in the same channel block, and wherein the channel block assigned for each segregated segment of the first wireless communication coverage unit is different from the channel block assigned for the segregated segment of a second wireless communication coverage unit that immediately borders with the segregated segment of the first wireless coverage unit even if the first and second wireless communication coverage units share the same frequency spectrum.

A method for estimating symbol sequences from multiple transmitters which communicate with common receivers sharing the same medium is disclosed. This invention can be used in wireless communications and wireline communications such as in cable modem sys terms and digital subscriber loops to speed up joint detection of symbol sequences of multiple transmitters to achieve low error probability. For convenience, only applications of this invention to wireless communications employing multiple antennas are described herein. The requirement for matrix operations like matrix inverses increase with the logarithm of the number of symbols instead of the number of symbols as with techniques based on Cholesky decomposition.

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Richardson, TX, United States of America

Weidong Yang