In this paper, a trellis-coded generalized spatial modulation scheme with spatial multiplexing is presented to achieve higher spectral efficiency. A joint detector for information bits in the spatial domain and constellation domain is also designed. Both the advantages of the Viterbi algorithm for detecting trellis-coded information bits and the sphere decoding algorithm for detecting spatial multiplexing signals can be exploited. Compared with the conventional trellis-coded generalized spatial modulation with duplicate signals being transmitted from the selected antennas, our scheme has better system performance given the same spectral efficiency.