A virtual layered signal processing receiver for 16-QAM with transmit signal rotation

This paper proposes a novel receiver, named as “a virtual layered signal processing receiver for 16 QAM” for high speed signal transmission in wireless communication systems. In the proposed receiver, the ordered successive detection is applied with the concept of virtual channel, which enables to detect layered streams even when the number of the layered streams is more than that of the received antennas. Therefore, the proposed receiver can increase the transmission speed of the down link in which a receiver is implemented in small terminals with a small number of antennas. The proposed receiver unfortunately degrades compared with the maximum likelihood estimation (MLD), however, when the channel matrix of the virtual channel is not full rank. To avoid the performance degradation, this paper proposes a technique that transmit signal constellation is phase-rotated with information fed back from the receiver. Actually, it is confirmed by computer simulation that only 1-bit of feed back information is enough to achieve the upper bound in BER performance in a 2 × 1 MIMO system.