Interdigital Technology Corporation

Interdigital Communications Corporation

Younglok Kim

Ariela Zeira

Jung-Lin Pan

Alexander Reznik

Donald M Grieco

Stephen G Dick

Sung-Hyuk Shin

Nader Bolourchi

John W Haim

Robert A DiFazio

Hyun-Seok Oh

Kyle Jung-Lin Pan

Ryan Samuel Buchert

Chayil S Timmerman

Jung Lin Pan

Pan Jung-Lin

Ariela Ziera

The present invention is a receiver which includes a blind code detection device for determining the identity of a plurality of channels over which information is to be transmitted when the identity of all channels is not known by the receiver. The blind code detection device generates a candidate channel list filled with the identify of selected channels out of the plurality of channels. A multi-user detection device, responsive to the blind code detection device, processes those channels in the candidate code list.

Method and apparatus for blind code detection

A base station and user equipment (UE) for use in a CDMA communication system are disclosed. The base station includes a first and second antenna for transmitting first and second communication bursts. The first channelization device spreads data using a first channelization code and the second channelization device spreads the data using a second channelization code. The UE has a data detection device for receiving a signal including the first and second communication bursts.

Simple block space time transmit diversity using multiple spreading codes

A method and apparatus for interference signal code power noise variance estimation employing a reduced number of samples is disclosed. A recursive technique may be employed wherein the noise variance is estimated from ignored coefficients of the estimated channel output and upgraded recursively.

Method and apparatus employed in a user equipment for interference signal code power and noise variance estimation

A plurality of communication signals is received. Each communication signal has an associated code. At least two of the communication signals has a different spreading factor. The associated codes have a scrambling code period. A total system response matrix has blocks. Each block has one dimension of a length M and another dimension of a length based on in part M and the spreading factor of each communication. M is based on the scrambling code period. Data of the received plurality of communication signals is received using the constructed system response matrix.

Data detection for codes with non-uniform spreading factors

Data is estimated from a received vector comprising a plurality of communications. A received wireless signal is converted to a baseband signal, which is sampled to produce a received vector. Channel responses are estimated for the received communications. The noise variance is estimated. The noise variance is scaled by a scaling factor. Samples are processed using the estimated channel responses and the scaled noise variance to produce a spread data vector. The spread data vector is despread to recover the data of the received wireless signal.

Scaling using gain factors for use in data detection

A criterion for biasing a binary decision requiring an unequal protection which utilizes a measured signal to interference ratio (SIR). The SIR may be derived from a determination of channel estimation. The SIR is compared against a threshold, the threshold being selected to bias the decision toward a not acknowledge (NACK) as opposed to an acknowledge (ACK) determination. The technique is advantageous for providing biased binary decisions for high speed downlink packets (HSDP) but may be utilized for both uplink and downlink applications.

Method and apparatus for providing biasing criteria for binary decisions for use in wireless communications to enhance protection

A method for the simultaneous reception of data from multiple sources having different spreading factors. A plurality of transmission response matrices are generated and grouped together for equal spreading factors. A plurality of spreading factor group matrices are assembled. A base matrix is formed based upon the spreading factor group matrix having a lowest spreading factor. An additional spreading factor group matrix is selected for consideration. Column placement reference index for the base matrix is derived. A reference location for the base matrix is derived. A column set from the selected spreading factor group matrix is derived. The column set is inserted into the base matrix. A total transmission response matrix is assembled.

Method for receiving communication signals having differing spreading factors

A plurality of communication bursts are transmitted substantially simultaneously in a time slot of a time division duplex/code division multiple access communication system. The communication system has a maximum number of K midamble shifts. Each burst has an assigned midamble. Each midamble is a shifted version of a basic midamble code having a period of P. A combined signal is received. The combined signal includes a received version of each of the communication burst's midambles. A P by P square circulant matrix is constructed including the K midamble shifts. A channel response is determined for each of the K midamble shifts using a prime factor algorithm (PFA) discrete Fourier transform (DFT) algorithm, the received combined signal and the P by P square circulant matrix. The PFA DFT algorithm has a plurality of stages. Each stage has P inputs.

Channel estimation in a wireless communication system

A receiver includes a blind code detection device for determining the identity of a plurality of channels over which information is to be transmitted when the identity of all channels is not known by the receiver. The blind code detection device generates a candidate channel list filled with the identity of selected channels out of the plurality of channels. A multi-user detection device, responsive to the blind code detection device, processes those channels in the candidate code list.

Method and apparatus employed by a UE for interference signal code power noise variance estimation employing a reduced number of samples utilizing the equation where whereN=L&#x2212;N&#xb7;K,where and where  As an alternative, a recursive technique may be employed wherein the noise variance is estimated from the ignored coefficients of the estimated channel output and upgraded recursively as per the following: where &#x125;are the channel estimates after the post processing and the noise variance estimates {circumflex over (&#x3c3;)}, and the initial values of &#x125;are all zeros.

The present invention is a method and system for receiving data transmitted using block space time transmit diversity (BSTTD) in a code division multiple access (CDMA) communication system. The system comprises a transmitter, for transmitting a first data field using a first antenna and a second data field using a second antenna, and a receiver. The receiver includes an antenna for receiving the first and second transmitted data fields, and a BSTTD joint detector which determines symbols of the first and second transmitted data fields using a minimum mean square error block linear equalizer model and an approximated Cholesky decomposition of the model.

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Seoul, South Korea

Younglok Kim