求翻译：下面对多径传播作定量分析。扩频带宽为1.228MHz的IS-95蜂窝系统和PCS系统可以分辨时延差异略小于1μs的多径信号。在室外环境中，时延可能有好几个μs，因此一些多径信号要采用Rake技术加以分辨和接收，但室内信道中多径时延常为ns级，它无法在相对窄带的IS-95信道中进行分辨，因此类似IS-95这样的系统必须克服严重的Rayleigh衰落，它要求信号必须在静态信号级的20dB以上，才能达到规定的性能。而带宽超过1GHz的UWB系统，能分辨出时延小于1ns的多径信号，然后采用Rake接收机可获得足够的信号能量。是什么意思？

Multipath propagation, the following quantitative analysis. The spread spectrum bandwidth for 1.228mhz is-95 cellular systems and pcs system can distinguish the delay difference is slightly less than 1 μs multipath signals. In outdoor environments, the delay may have several μs, so some multipath si

The multi-path propagation for quantitative analysis. The band width of 1.228 MHz IS - 95 of the cellular systems and PCS resolution system can be extended when you difference a little less than 1 µs of multi-path signal. In the outdoor environment, time delay may be a few µs, and some multi-path si