Method and communication device for interference cancellation in a cellular TDMA communication system
View Patent ↗A system and method for interference cancellation of received data via a communication channel in a cellular communication system having corresponding channel impulse response coefficients. Linear filtering of the received data is performed and thereafter a non-linear detection is executed to get detected data by non-linear signal processing. Filter coefficients are determined for linear pre-filtering of the received data to suppress non-Gaussian interference. The pre-filtered data is further processed by non-linear detection to get detected data.
1. A method for interference cancellation of data received via a communication channel in a cellular communication system having corresponding channel coefficients, the method comprising:
(a) performing linear pre-filtering of the received data using at least one processing unit;
(b) determining linear pre-filter coefficients for linear pre-filtering of the received data using the at least one processing unit, wherein the pre-filter coefficients are used to suppress non-Gaussian interference during filtering of the received data;
(c) determining optimized channel coefficients using the linear pre-filter coefficients; and
(d) determining detected data by:
(i) using the at least one processing unit, performing non-linear detection via signal processing; and
(ii) using the optimized channel coefficients as an input when performing the non-linear detection.
2. The method of claim 1 , which includes determining the optimized channel coefficients based on a maximum value of a signal-to interference/noise ratio.
3. The method of claim 2 , wherein the optimized channel coefficients are determined by a convolution between the linear pre-filter coefficients and the channel coefficients for a desired user.
4. The method of claim 3 , wherein the optimized channel coefficients are determined by a channel estimator that uses pre-filtered data.
5. The method of claim 1 , which includes determining the optimized channel coefficients for a non-linear equalizer by convolution of the filter coefficients using estimated channel coefficients of desired data.
6. The method of claim 1 which includes processing of pre-filtered data using a memory-less detector, using a backwardly directed filter of a Minimum Mean Square Error-Decision-Feedback Equalizer (MMSE-DFE) in connection with the memory-less detector.
7. The method of claim 1 , wherein performing non-linear detection includes processing of the pre-filtered data using a non-linear equalizer.
8. A communication device for communicating to users in a cellular communication network, the communication device comprising:
a receiver unit that receives:
(a) first data sent from another device over a communication channel; and
(b) second data sent from at least one further device via an interfering channel, wherein the channels have corresponding channel coefficients in relation to a desired user; and
at least one processing unit coupled to a memory, the memory storing instructions that, when executed by the processing unit, cause the processing unit to:
(a) performs linear pre-filtering of the received first and second data;
(b) determines linear pre-filter coefficients for linear pre-filtering of the received first and second data, wherein the filter coefficients are used to suppress non-Gaussian interference during filtering of the received first and second data;
(c) determines optimized channel coefficients using the linear pre-filter coefficients; and
(d) determines detected data by:
(i) performing non-linear detection via signal processing; and
(ii) using the optimized channel coefficients as an input when performing the non-linear detection.
9. The communication device of claim 8 , wherein one of the at least one processing unit is a linear pre-filter for suppressing non-Gaussian interference, followed by a non-linear detector to cancel intersymbol interference.