Joint Map Equalization and Channel Estimation Forfrequency - Selective Fast -
نویسندگان
چکیده
This paper presents a maximum a posteriori (MAP) equalizer for bandlimited signals on frequency selective fading channels. A key contribution is the way in which the state-space of the MAP trellis is expanded for the purpose of joint channel estimation and equalization. The fading channel is estimated by coupling minimum mean square error techniques with the expanded MAP trellis. The symbol-by-symbol MAP algorithm is a soft-input soft-output technique. The new MAP receiver can also be applied to iterative (turbo) decoding. Simulations demonstrate the performance of the proposed demodula-tor. Both uncoded systems and turbo coded systems with frequency selective channels are studied.
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