A Recording Of SIC Algorithm In The Application Of VAMOS

As a kind of time slot multiplexing technology, VAMOS systems are widely used for increasing wireless capacity in the global system for mobile communications (GSM) network。 The target user is equivalent to a fixed frequency interference, because of one time slot multiplexing two users in VAMOS system. The same frequency interference will produce very big effect to the target user. So VAMOS system depends largely on the performance of the receiver signal detection algorithm, namely multi-user detection technology.Because of better performance, easy implementing and less hardware change, SIC is widely used in VAMOS system, as a multi-user detection technology. Different power level between multi-users will obtain the best effect. When the power is very similar between two users, the signal stripping of strong user will bring a great influence to other users, even lead to failed demodulation of weak users.A recoding SIC algorithm is designed in this thesis, to enhance accuracy of eliminating the strong user. And the application is implemented on the simulation of VAMOS system. Firstly, the VAMOS system are introduced, to explain the important role of SIC algorithm in VAMOS system. Secondly, the principle, advantages and disadvantages of SIC algorithm are discussed. Then, the convolutional coding and Viterbi decoding are description. Mainly discusses the advantage of error correction and the coding gain.Finally, the recoding SIC algorithm is designed in this thesis, as an improved method of SIC.The performance are tested in the simulation of VAMOS system, and the results indicate that the requirement of system can be satisfied.