A Low Complexity Decision Directed Adaptive Receiver for MIMO Communication Systems

An Adaptive algorithm is demonstrated in this paper for MIMO communication receivers. We utilize a decision directed adaptive filter with an integrated logarithmic codec. The anticipated area of impact is for low power Wireless Sensor Networks that are not equipped with hardware comparable to cellular communication devices. The receiver can operate reliably with low Quantization resolution and it is shown to performs similar to a device equipped with high fidelity quantization. This applies when the SNR and the Misadjustment of the adaptive filter serve as performance bottlenecks. The logarithmic codec integrated into the adaptive filter has an accuracy similar to that of a traditional ALU with only four bits of precision. Provided the channel is noise rather than interference (and correspondingly mean square error (MSE)) limited then the receiver proposed in this paper operates with a loss of approximately 1dB in a 20×10 MIMO Wireless Channel compared with an ideal LMS implementation.