Transmitter-assisted joint data-aided channel estimation and PAPR reduction scheme in wireless fading channels

This paper presents a novel transmitter-assisted joint scheme that simultaneously addresses two critical challenges in modern wireless communication systems: peak-to-average power ratio (PAPR) reduction and accurate channel estimation. The proposed solution integrates modified gamma correction commanding (MGCC) with data-aided channel estimation (DACE) for both single-input single-output (SISO) and multiple-input multiple-output (MIMO) orthogonal frequency-division multiplexing (OFDM) wireless systems. The key novelty lies in the unique dual-functionality approach, where high-peak power carriers, traditionally a source of distortion due to high PAPR, are repurposed as additional pilot signals at the receiver for improved channel estimation. This innovative use of MGCC not only optimizes the identification and utilization of these carriers but also ensures that the selection of reliable data carriers remains unaffected. By transforming the high PAPR problem into a performance advantage, the scheme significantly reduces the computational complexity typically associated with separate PAPR reduction and channel estimation processes, making it particularly suitable for low-complexity wireless devices. The proposed approach determines peak-powered subcarriers entirely from the transmitted signal, eliminating the need for receiver-to-transmitter feedback and thereby simplifying system design without compromising performance. Furthermore, the study identifies optimal companding parameters to achieve an effective balance between error performance and PAPR reduction. Extensive simulations under Rayleigh and Rician fading channels with varying tap configurations demonstrate the robustness and versatility of the proposed scheme. Performance evaluations, including mean square error and bit-error-rate analyses, confirm the superiority of the proposed approach when paired with least square and linear minimum mean square error channel estimators. The impact of receive antenna correlation on error performance is also analyzed, revealing a nonlinear trend where low correlation levels have minimal effect, while variation in correlation influences system behavior. The results highlight consistent and reliable performance across diverse fading environments, underscoring the potential of the proposed scheme to enhance the efficiency and reliability of next-generation wireless communication systems.