Popis: |
In this paper, a rapid signal-acquisition method is proposed for carrier-based ultra-wideband impulse-radio systems in low-data-rate applications such as sensor networks. For low-data-rate ultra-wideband impulse radio systems, highly precise synchronization must be established over relatively long periods. In the proposed method, signal-acquisition times are reduced by assigning different blocks responsibility for synchronization with the pulse and with the spreading code. Furthermore, dividing up the symbols to produce a smaller unit for integration enables signal acquisition even when there is a realistic difference between the transmitter and receiver-local frequencies. Results of simulation indicate that, for a given Eb/N0, the proposed method reduces acquisition times from those required by the conventional method. |