Constant modulus single antenna interference cancellation for GSM

In cellular systems, interference suppression at the mobile receiver can be used to improve the downlink performance and capacity. We investigate single antenna interference cancellation (SAIC) at the receiver for a GSM/EDGE system with GMSK modulation. An interference suppression technique, which exploits the constant envelope property of the GMSK modulated signal, was proposed by Berangi et al in (Wireless Pets. Commun., Kluwer Acad. Pub., no.19, p.37-55, 2001). We observed that such technique is very sensitive to channel estimation error and hardly provides any gain when least square (LS) channel estimation is employed. Therefore, we study the performance of constant modulus single antenna interference cancellation (CM-SAIC) with multi channel estimation and show that significant performance improvement can be achieved. In the presence of a single dominant interfering signal, we obtain up to 7 dB gain in the TU3 channel.