A scheme of multi-user reusing one slot on enhancing capacity of GSM/EDGE networks

GSM network is seeing its greatest expansion because of the growing demand for mobile voice services in emerging markets recently. A newly proposed technology, multiuser reusing one slot (MUROS), would help operators in densely populated cities to alleviate the strain on their networks. The concept of MUROS is based on multiplexing two or more users onto one time slot without degrading the speech quality. We improved one solution of MUROS, orthogonal sub channel (OSC) in this contribution. For the downlink (DL) OSC, we designed new training sequence codes (TSCs) which are low cross-correlated with legacy TSCs. For the uplink (UL) OSC, we adopted successive interference cancellation based on minimum mean square error (MMSE-SIC) algorithm. Theoretical analysis and simulation results shows that with proper TSC design, OSC is a promising scheme of MUROS due to its ability to double the capacity of GSM/EDGE networks without degrading the speech quality very much.