Layered data transmission based on training sequences in TDS-OFDM system

In order to realize multi-service application in the time domain synchronous orthogonal frequency division multiplex (TDS-OFDM) system, a layered data transmission scheme is proposed in this paper. This scheme allows for the transmission of different services over the same bandwidth with different transmission qualities. Concretely, the second layer data stream is transmitted through modulation on training sequence, and has lower receiving sensitivity and larger coverage area. So it can be used to support mobile service, such as local news, weather. While the first layer data stream is sent as the conventional TDS-OFDM scheme. Theoretical analysis and computer simulation show that the proposed scheme works well and these two layer data streams are compatible with each other.