A Low Complexity Turbo Equalizer
نویسندگان
چکیده
In this paper a new Soft Input Soft Output (SISO) equalizer of linear complexity is developed. The algorithm can be used in the so-called Turbo Equalization scheme as a low cost solution in place of the Maximum A-Posteriori (MAP) equalization algorithm which has a prohibitive complexity for most real world applications. The proposed equalizer consists of two parts, namely, a Soft Interference Canceller (SIC) and a pre-processing part which is a new Variable-Threshold Decision Feedback Equalizer (VTDFE). The main difference in the proposed equalizer as compared to the SIC is that the input to the cancellation filter is computed not only using a-priori probabilities, but information from the received signal as well. Simulation results have shown that the proposed turbo equalizer exhibits a superior performance as compared to the turbo equalization scheme based on the conventional SIC as well as other linear complexity SISO equalizers.
منابع مشابه
Implementation of a Low-Complexity MMSE Turbo-Equalizer on the TMS320VC5509
This report describes the implementation of a low-complexity minimum mean-square error (MMSE) turbo-equalizer on Texas Instruments TMS320VC5509 device, a low-cost 16-bits fixed-point DSP with low power consumption designed for mobile handsets. A data rate of 207 Kbits/s per iteration has been obtained with programming mainly in C. With carefully optimized data quantization, the resulting fixed-...
متن کاملLow - Power Turbo Equalizer Architecture
In this paper, we propose a low complexity architecture for turbo equalizers. Turbo equalizers jointly equalize and decode the received signal by exchanging soft information iteratively. The proposed architecture employs early termination of the iterative process when it does not impact the bit-error rate PER). Early termination enables the powering down parts of the soft-input soft-output (SIS...
متن کاملFixed-Point Implementation of an Efficient Low-Complexity Turbo-Equalization Scheme
This paper investigates the realization of an efficient low-complexity turbo-equalizer under fixedpoint data representation and computation constraints. We address the quantization issues that arise in the receiver design, and expose a simple computation procedure for the equalizer coefficients. The proposed solution is well-suited for a DSP implementation on low cost 16 bits fixed-point device...
متن کاملA low complexity approach to Turbo Equalizer
The turbo equalizers (TEQ) proposed in literature utilize equalizers based on trellis, soft Wiener filters. The resulting complexity of these equalizers is exponential and cubic in terms of the sampled channel impulse response (CIR). The interference cancellation based decision feedback filter based equalizers requires adaptation of two filters simultaneously. In this paper, a low complexity eq...
متن کاملLow Complexity data transmission over wireless system
It is proposed low-complexity block turbo equalizers for orthogonal frequency-division multiplexing (OFDM) system in a channel. The presented work is based on a soft minimum mean –square error (MMSE) block linear equalizer (BLE) that exploits the banded structure of the frequency –domain channel matrix, as well as a receiver window that enforces this banded structure. This equalization approach...
متن کامل