Читать книгу Spatial Multidimensional Cooperative Transmission Theories And Key Technologies - Lin Bai - Страница 28

In Section 2.1.1, we briefly introduced how to use the different criteria to obtain the optimal linear combination vector to design different signal combinations. Under ideal conditions, we can assume that the receiver can only receive the target signals. However, the receiver actually often receives interference signals from other devices while receiving the target signals. For these interference signals, traditional signal combining methods generally classify them into noise for processing, but such solutions have obvious drawbacks and sometimes lead to large performance losses.

As a result, the method of extracting the target signal in the mixed signal, namely the signal detection method, is beginning to be studied. Multi-signal detection method has always been an important problem to be solved in wireless communication. As shown in Fig. 2.2, in a cellular system, if users in two cells use the same transmission channel to transmit signals, the base station can receive the user signal in the cell of the base station and can also receive the signal in another cell. And in this case, the base station needs to detect different signals. In addition, when a transmitter transmits signals through multiple transmitting antennas, the receiving end also needs to detect multiple received signals. And when multiple antennas are used by both the transmitter and the receiver, point-to-point signal detection can also be regarded as a virtual multi-signal detection technique due to interference between the antennas. In addition, when multiple antennas are used by both the transmitter and the receiver, point-to-point signal detection can also be regarded as a virtual multi-signal detection technology due to the interference between the antennas.

Fig. 2.2. Multi-user monitoring model of the cellular system.

The above examples illustrate several common application scenarios for multi-signal detection, and multi-signal detection technology will play a significant role for a long time.