| 摘要 |
The invention relates to improvements of spread spectrum GMSK (Gaussian Minimum Shift Keying) signals, particularly to method for generating a spread spectrum Gaussian Minimum Shift Keying, GMSK, signal comprising obtaining a sequence D(t) of data symbols for a data channel, obtaining at least one first spread spectrum code comprising a first sequence C D (t) of spread spectrum chips for the data channel, obtaining at least one second spread spectrum code comprising a second sequence C P (t) of spread spectrum chips for a pilot channel, generating a sequence r(t) of premodulation chips by combining the sequence D(t) of data symbols for the data channel with the spread spectrum chips of the first sequence C D (t) of the at least one first spread spectrum code and data symbols for the pilot channel with the spread spectrum chips of the second sequence C P (t) of the at least one second spread spectrum code to a combined sequence of chips, assigning the chips of the combined sequence of chips to the transmission channels In-Phase I and Quadrature Q of the spread spectrum GMSK signal so that not more than two consecutive pre-modulation chips generated with the same spread spectrum code are transmitted in the same transmission channel I or Q, and performing GMSK modulation g(t) using the sequence of pre-modulation chips to generate a spread spectrum GMSK signal s(t). |
