A method based on linear congruential generator (LCG) is used to construct random interleavers for interleave-division multiple-access (IDMA). One interleaver, called the mother interleaver, is first generated and then cyclically shifted to obtain the other interleavers, each belonging to one user. We propose to choose the LCG parameters such that its maximum period is reached and, for convenience, the LCG modulus is a power of 2. With these settings, the modulus should be strictly greater than the interleaver size. A mathematical proof is provided for this matter. Out-of-bound random numbers are simply discarded. Finally, peak basis correlation and bit-error rate analysis are used to show correctness of the theoretical expectations.%提出一种基于线性同余生成器(LCG)来构造IDMA系统中随机交织器的方法.该方法通过选择LCG的参数使其周期达到最人.为了设计方便,取LCG的模为2的整数幂.利用文中的方法产生母交织器,再对其进行循环移位,即得到每个用户的交织器.其中超出交织范围的随机数将被丢弃.数学推导证明,在上述条件下LCG的模必须严格大于交织器的深度.利用基向量相关峰值方法和误比特率性能证明了文中方法的有效性.
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