Abstract:To overcome difficulties of high complexity and modulation index estimation in conventional Multi-h Continuous Phase Modulation(Multi-h CPM), a new Multi-h CPM signals format based on tamed spread spectrum technique is proposed, which can obtain similar phase state trellis structure and performance gain as conventional Multi-h CPM signal. Moreover, the modulation index synchronization can be completed while the pseudo random spreading sequence is synchronized. The paper provides the Euclidean distance expression and searches the minimum distance of h=5/7. It shows that the proposed signal format can obtain 0.5 dB gain in terms of minimum Euclidean distance compared with the conventional Direct Sequence Spread Spectrum(DSSS) Single-h CPM. The synchronous de-spreading and demodulation algorithm based on Maximum Likelihood Sequence Detection(MLSD) can be used for optimum receiver. Numerical results show that tamed spread spectrum Multi-h CPM signal format can obtain a performance gain of 1.5 dB with a Bit Error Rate(BER) of 10-5 compared to DSSS Single-h CPM. Moreover, it outperforms WGS and ARTM Tier2 system.