An Improved Channel Estimation Technique for IEEE 802.11p Standard in Vehicular Communications

Abstract

IEEE 802.11p based Dedicated Short-Range Communication (DSRC) is considered a potential wireless technology to enable transportation safety and traffic efficiency. A major challenge in the development of IEEE 802.11p technology is ensuring communication reliability in highly dynamic Vehicle-to-Vehicle (V2V) environments. The design of IEEE 802.11p does not have a sufficient number of training symbols in the time domain and pilot carriers in the frequency domain to enable accurate estimation of rapidly varying V2V channels. The channel estimation of IEEE 802.11p is preamble based, which cannot guarantee a suitable equalization in urban and highway scenarios, especially for longer length data packets. This limitation has been investigated by some research works, which suggest that one major challenge is determining an accurate means of updating channel estimate over the course of packet length while adhering to the standard. The motivation behind this article is to overcome this challenge. We have proposed an improved Constructed Data Pilot (iCDP) scheme which adheres to the standard and constructs data pilots by considering the correlation characteristics between adjacent data symbols in time domain and adjacent subcarriers in frequency domain. It is in contrast to previous schemes which considered the correlation in the time domain. The results have shown that the proposed scheme performs better than previous schemes in terms of bit error rate (BER) and root-mean-square error (RMSE).

Low Complex Methods for Robust Channel Estimation in Doubly Dispersive Environments

“…Table 4 shows a detailed summary of the computational complexities for studied estimators. We note that the detailed calculation of TRFI, CDP, iCDP estimators is presented in [9], [24].…”

“…CDP estimator outperforms STA estimator especially in high SNR region but still cannot perform well in high mobility scenarios when high modulation orders are employed. Improved CDP (iCDP) [9] estimator combines both STA and CDP estimators, thus the overall performance in the whole SNR region is improved. In [10], the authors proposed the time domain reliable test frequency domain interpolation (TRFI) estimator that utilizes frequency domain interpolation in order to also improve the CDP estimator.…”

Visible Light Communication with Input-Dependent Noise: Channel Estimation, Optimal Receiver Design and Performance Analysis

“…Channel estimation is crucial for the performance of any wireless communication system, i.e., accurate estimation is essential for the follow-up equalization, demodulation, and decoding. Therefore, an accurate estimator leads to reliable communication systems [39].…”

“…where denotes the channel estimation error. The SER of -PAM can be obtained by substituting (39) into (33). Moreover, the OOK BER can be rewritten as…”

Estimation of Compressible Channel Impulse Response for OFDM Modulated Transmissions

“…Comb pilots transmitted in the remaining OFDM symbols are necessary to keep synchronization and track channel variations using interpolation methods. An implementation example of the abovementioned frame structure can be found in 802.11 standards' family [5,6]. A similar frame configuration seems to be appropriate in any simple OFDM transmission scheme including various proprietary solutions designed for IoT, industrial, or military-oriented applications.…”