Monthly Archives: January 2020

Orthogonal Minimum Shift Keying (OMSK)

Some Background

Before we delve deep into Minimum Shift Keying (MSK) and its performance in presence of co-channel interference the reader is advised to look at the following posts.

Post 1 – MSK BER performance in AWGN and flat fading environment when viewed as extension of BPSK

Post 2 – MSK Power Spectral Density and its BER performance in AWGN when viewed as a CPM

Post 3 – MSK BER Performance in AWGN and flat fading environment when viewed as a CPM

Co-channel interference is a phenomenon widely encountered in wireless communication systems and the main reason for that is frequency reuse, which allows the same frequency band to be used over and over again in geographically non-contiguous areas. GSM and other wireless communication systems, using MSK modulation, suffer from the same problem. This has been widely studied in the literature and interference rejection techniques have been proposed. The worst case is one where the power of both the signals (wanted signal and interference) is almost the same and there is no frequency or phase offset. 
Continue reading Orthogonal Minimum Shift Keying (OMSK)