A novel FHSS multiple-access network using M-ary orthogonal Walsh modulation
Joonyoung Cho, Youhan Kim, Kyungwhoon Cheun · 2002
A novel frequency-hop spread-spectrum multiple-access (FHSS-MA) network employing M-ary orthogonal Walsh sequence keying with noncoherent demodulation is proposed. The Walsh sequence is overlaid by a user specific PN sequence to reduce the effects of multiple-access hits. Two Gaussian approximations for the multiple-access interference from both the dehopped slot and its neighboring slots are developed. These are used to analyze the performance of the proposed network for synchronous and asynchronous hopping under nonfading and Rayleigh fading channels. It is shown that the proposed network significantly improves the maximum achievable normalized throughput compared to networks employing traditional MFSK.