Iterative estimator and method of channel and noise variance for multiple input multiple output orthogonal frequency division multiplexing system

A repeat channel noise variation estimate device and a method for multiple input/output orthogonal frequency division system are provided to improve the function and lower the complexity. A repeat channel for multiple input/output orthogonal frequency division system comprises: a encoder, interleaving unit, mapping unit, pilot insertion unit, and transmission antenna. The encoder encodes transmission packet. The interleaving unit performs interleaving of encoded transmission packet. The mapping unit performs the mapping of the transmission packet. The pilot insertion unit inserts pilot symbol and information symbol.