METHOD AND SYSTEM FOR MULTIUSER WIRELESS COMMUNICATIONS USING ANTI-INTERFERENCE TO INCREASE TRANSMISSION DATA RATE

• US 20080219209A1
• Filed: 05/23/2008
• Published: 09/11/2008
• Est. Priority Date: 12/03/2003
• Status: Active Grant

• Current Assignee: Rendong Ying, Ruey-Wen Liu
• Original Assignee: Rendong Ying, Ruey-Wen Liu
• Inventors: LIU, Ruey-Wen, YING, Rendong
• Granted Patent: US 7,903,617 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04B 1/126 having multiple inputs, e.g. auxiliary antenna for receiving interfering signal aerials in general H01Q

Abstract

A method and system for multi-user wireless communications between a sender and a receiver enables effective blocking of interference signals by other senders and improving the channel data rate. The receiver uses two or more receiving devices, such as antennas or smart antennas, to receive multiple wireless input signals. By performing a noise-transparent autocorrelation matching analysis on the multiple input signals, the receiver derives an anti-interference filter for interference-blocking action, without the need for information of the interfering and its transmission channel. In a multi-user environment, the noise-transparent autocorrelation matching analysis is implemented by the Autocorrelation Division Multiple Access (ADMA) system that includes the design and the implementation of ADMA code, the ADMA encoder, the ADMA algorithm and the ADMA decoder.

Claims

1. A method of transmitting data in a multiple access communications network, the method comprising:

generating a unique autocorrelation division multiple access (ADMA) code, from a set of ADMA codes such that no pair in the set are linearly dependent, for reducing interference in a data transmission to at least one user device connected to the multiple access communications network;

sending the unique ADMA code for the user device from a transmitter to a receiver;

encoding an original data stream using an ADMA encoder using the unique ADMA code such that an encoded data stream is created;

transmitting the encoded data stream to the receiver;

filtering interference from the encoded data stream to obtained a substantially interference-free encoded data stream using an ADMA filter which is a closed form solution derived by a noise-transparent autocorrelation matching analysis and incorporating the unique ADMA code; and

decoding the substantially interference-free encoded data stream by an ADMA decoder such that the original data stream is substantially obtained.

2. The method of claim 1 further comprising storing the unique autocorrelation multiple access code for each user device connected to the multiple access communications network.

3. The method of claim 1 wherein the step of encoding the original data stream further comprises an ADMA encoder that is invertible and that has the property that the autocorrelation of the encoded data stream is the same as the unique ADMA code on a noise-transparent set of time-lag variables.

4. The method of claim 1 wherein the step of encoding the original data stream further comprises using an ADMA encoder that is invertible and that has the property that the autocorrelation of the encoded data stream is the same as the unique ADMA code on a noise-transparent set of time-lag variables.

5. The method of claim 1 wherein the filtering step further comprises computing a weighted sum of the encoded data stream.

6. A computer readable medium having computer executable instructions for transmitting data in a multiple access communications network having a remote node for generating a unique autocorrelation division multiple access (ADMA) code for reducing interference in a data transmission to at least one user device connected to the multiple access communications network and encoding an original data stream using an ADMA encoder using the unique ADMA code such that an encoded data stream is created, the computer executable instructions comprising

instructions for receiving the unique ADMA code from the remote node;

instructions for receiving the encoded data stream from the remote node;

instructions for filtering interference from the received encoded data streams to obtained a substantially interference-free encoded data stream using an ADMA filter which is a closed form solution derived by a noise-transparent autocorrelation matching analysis and incorporating the unique ADMA code;

instructions for decoding the substantially interference-free encoded data stream by an ADMA decoder such that the original data stream is substantially obtained.

7. The computer readable medium according to claim 6 wherein the instructions for filtering interference further include instructions for computing a proper weighted sum of the received encoded data streams.

8. The computer readable medium according to claim 6 wherein the instructions for encoding further comprise instructions for implementing an ADMA encoder that is invertible and that has the property that the autocorrelation of the encoded data stream is the same as the unique ADMA code on a noise-transparent set of time-lag variables.

9. A system for transmitting data in a multiple access communications network, the system comprising:

a transmitter node comprising a processor configured to generate a unique autocorrelation division multiple access (ADMA) code for reducing interference in a data transmission to at least one user device connected to the multiple access communications network and an encoder configured to receive an original data stream and produce an encoded data stream using an ADMA encoder and the unique ADMA code for the at least one user device;

the at least one user device comprising;

a receiver configured to receive the encoded data stream from the transmitter node;

an ADMA closed form filter derived by a noise transparent autocorrelation matching analysis, the ADMA closed form filter incorporating the unique ADMA code and producing a substantially interference free encoded data stream;

a decoder that produces a substantially the original data stream from the substantially interference-free encoded data stream.

10. The system of claim 9 wherein the multiple access communications network is one of a cellular network, a computing network having a router or an ad hoc network.

11. The system of claim 10 wherein the at least one user device is a computer.

12. The system of claim 9 wherein the transmitter node is one of a computer router or a cellular base station.