# US 2014/0153494 A1 · System and Method for Reducing Interference in Wireless Communication Systems > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0153494 A1 - Document ID: US20140153494A1 - Status: Published application - Kind: A1 - Application number: 14/173,042 - Filed: 2014-02-05 - Published: 2014-06-05 - Earliest claimed: 2012-09-27 - Inventors: Rueywen Liu - Web page: https://patentgrep.com/patent/US20140153494A1 ## CPC - H04W 24/02: Arrangements for optimising operational condition - H03H 21/0027: {filtering in the frequency domain} - H04B 1/10: Means associated with receiver for limiting or suppressing noise or interference - H04B 1/109: {by improving strong signal performance of the receiver when strong unwanted signals are present at the receiver input} - H04B 1/12: Neutralising, balancing, or compensation arrangements - H04B 1/126: {having multiple inputs, e.g. auxiliary antenna for receiving interfering signal (aerials in general H01Q)} - H04B 17/336: Signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR] - H04J 11/003: {at the transmitter (transmission to multiple receive units in multiple input multiple output [MIMO] H04B7/0452; transmit antenna weighting H04B7/0615)} - H04J 11/0036: {at the receiver} - H04B 3/32: Reducing cross-talk, e.g. by compensating - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H03H: IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS (waveguides, resonators, lines or other devices of the waveguide type H01P) - H04B: TRANSMISSION - H04J: MULTIPLEX COMMUNICATION (transmission in general H04B; peculiar to transmission of digital information H04L5/00; systems for the simultaneous or sequential transmission of more than one television signal H04N7/08; in exchanges H04Q11/00; stereophonic systems H04S) ## Abstract A system and method for mitigating interference in a physical layer is disclosed. The system may include a transmitter configured to transmit a message, the message having appended to it an interference signal and a receiver configured to receive the message from the transmitter. The receiver may also include a singular value decomposition filter receiver into which the message is input, the singular value decomposition filter receiver configured to use singular value decomposition data from the interference signal to recover the message from the transmitter while substantially eliminating the interference signal. The interference signal may be co-channel with the message and/or the interference signal may be dominant to the message. ## Claims ### Claim 1 A system for mitigating interference, the system comprising: a transmitter configured to transmit a message, the message having appended to it an interference signal; and a receiver configured to receive the message from the transmitter and input the message into a singular value decomposition filter receiver, the singular value decomposition filter receiver configured to use singular value decomposition data from the interference signal to recover the message from the transmitter while substantially eliminating the interference signal. ### Claim 2 (depends on 1) The system of claim 1, wherein the system is used to substantially eliminate the interference signal in a physical layer of an unlicensed wireless network. ### Claim 3 (depends on 1) The system of claim 1, wherein the singular value decomposition filter receiver comprises a fast Fourier transform block to convert the message into a frequency domain signal. ### Claim 4 (depends on 3) The system of claim 3, wherein the singular value decomposition filter receiver further comprises a data arrangement block configured to receive the frequency domain signal to determine an interference matrix. ### Claim 5 (depends on 4) The system of claim 4, wherein the communication between the fast Fourier transform block and the data arrangement block is controlled by opening and closing of a switch. ### Claim 6 (depends on 1) The system of claim 1, wherein the singular value decomposition filter receiver comprises a singular value decomposition block to determine a filter value computed from an interference matrix, the interference matrix determined by extracting singular value decomposition data from the interference signal. ### Claim 7 (depends on 6) The system of claim 6, wherein the singular value decomposition filter receiver further comprises a singular value decomposition filter correlator block that receives a frequency domain signal and the filter value as inputs and uses the filter value to substantially eliminate the interference signal from the message. ### Claim 8 (depends on 6) The system of claim 6, wherein the determination of the filter value occurs in a training stage before the singular value decomposition filter receiver can substantially eliminate the interference signal from the message. ### Claim 9 (depends on 1) The system of claim 1, wherein the singular value decomposition filter receiver is further configured to substantially eliminate the interference signal when the interference signal includes a noise signal. ### Claim 10 (depends on 1) The system of claim 1, wherein the singular value decomposition filter receiver can substantially eliminate the interference signal when the interference signal is thousand times than the message. ### Claim 11 A method for mitigating interference, comprising: transmitting a message from a transmitter to a receiver, the message having appended to it an interference signal; receiving the message and the interference signal at a receiver; inputting the message and the interference signal into a singular value decomposition filter receiver at the receiver; and eliminating substantially the interference signal from the message by the singular value decomposition filter receiver using singular value decomposition values from the interference signal. ### Claim 12 (depends on 11) The method of claim 11, wherein the singular value decomposition filter receiver converts the message and the interference signal into a frequency domain signal using a fast Fourier transform block. ### Claim 13 (depends on 12) The method of claim 12, wherein the frequency domain signal is input into a data arrangement block if a switch between the fast Fourier transform block and the data arrangement block is closed, the data arrangement block extracting the singular value decomposition values from the interference signal to determine an interference matrix. ### Claim 14 (depends on 11) The method of claim 11, wherein substantially eliminating the interference signal comprises determining a filter value by a singular value decomposition block, the filter value determined from an interference matrix. ### Claim 15 (depends on 11) The method of claim 11, wherein substantially eliminating the interference signal comprises utilizing a filter value by a singular value decomposition filter correlator of the singular value decomposition filter receiver to recover the message while substantially eliminating the interference signal. ### Claim 16 (depends on 11) The method of claim 11, wherein for an input signal to interference ratio of a negative thirty decibels, the singular value decomposition filter receiver provides an output signal to interference ratio of a positive two hundred decibels. ### Claim 17 A singular value decomposition filter receiver, comprising: a fast Fourier transform block to transform an incoming time domain signal into a frequency domain signal; a training stage to determine a filter value; and an operating stage to utilize the filter value and the frequency domain signal to substantially eliminate an interference signal appended to a message. ### Claim 18 (depends on 17) The singular value decomposition filter receiver of claim 17, wherein the training stage comprises: a data arrangement block configured to receive the frequency domain signal and determine an interference matrix by extracting singular value decomposition values of the interference signal from the frequency domain signal; and a singular value decomposition block configured to receive the interference matrix from the data arrangement block and determine the filter value from the interference matrix. ### Claim 19 (depends on 18) The singular value decomposition filter receiver of claim 18, further comprising a switch between the fast Fourier transform block and the data arrangement block, the switch being closed only in the training stage. ### Claim 20 (depends on 17) The singular value decomposition filter receiver of claim 17, wherein the operating stage comprises a singular value decomposition filter correlator that receives the frequency domain signal and the filter value from the training stage to recover the message while substantially eliminating the interference signal from the frequency domain signal.