For high-bandwidth and high-speed frequency hopping communication system, how to achieve real-timefrequency switching and wideband sampling in low cost is still a challenging problem. Multi-channel parallel receiver is a goodsolution for wideband signal sampling. A new multi-channel full-frequency parallel receiving system is proposed. A new two-stagedown frequency algorithm is proposed. The new proposal has low performance requirement for hardware devices. It is also simplefor engineering implementation.