A spread spectrum communication device, wherein an interleaver performs rearrangement in units of a bit over plural frames in a compression mode, a framing/spreading unit reduces the spreading rate and outputs a compression mode frame at a predetermined compression mode frame timing, a radio frequency transmitting unit amplifies the average transmission power in the compression mode. By establishing the synchronization with another frequency carrier based on detected first and second search codes, interfrequency handover is carried out; and by establishing the synchronization with GSM based on the detected FCCH and SCH, inter communication system handover is carried out.