Low-complexity carrier phase recovery based on principal component analysis for square-QAM modulation formats

Abstract

We propose, numerically analyze and experimentally demonstrate a low-complexity, modulation-order independent, non-data-aided (NDA), feed-forward carrier phase recovery (CPR) algorithm. The proposed algorithm enables synchronous decoding of arbitrary squarequadrature amplitude modulation (QAM) constellations and it is suitable for a realistic hardware implementation based on block-wise parallel processing. The proposed method is based on principal component analysis (PCA) and it outperforms the well-known and widely used blind phase search (BPS) algorithm at low signal-to-noise ratio (SNR) values, showing much lower cycle slip rate (CSR) both numerically and experimentally. For operation at higher SNR values, a hybrid two-stage implementation combining the proposed method and BPS is also proposed and their performance are investigated benchmarking them against the two-stage BPS (2S-BPS). The complexity of the proposed simple and hybrid methods are evaluated against 2S-BPS and computational complexity savings of 92% and 40% are expected for the simple and hybrid methods, respectively.

Energy-Efficient Implementation of Carrier Phase Recovery for Higher-Order Modulation Formats

“…A recently published CPR algorithm, called principal component-based phase estimation (PCPE) [12], uses principal component analysis to estimate the phase noise. In general, the PCPE algorithm requires less complex hardware than BPS does.…”

“…However, PCPE suffers from residual phase noise, which is especially pronounced at high signal-to-noise ratios (SNRs). The problem with residual phase noise can be mitigated by cascading PCPE with BPS, using a limited number of test phases [12].…”

Multi-Format Carrier Phase Recovery Using a Programmable Circuit

“…Based on the work done in [3] and [4], we have identified principal component-based phase estimation (PCPE) [5] to be a good choice for a multi-format CPR implementation, as it can handle multiple square QAM formats without any modification. Other popular algorithms, such as blind phase search [6] or versions of the Viterbi-Viterbi estimator [2], need larger circuit extensions to support multiple formats, resulting in a larger total area.…”

Adaptive EKF Based Estimation Method for Phase Noise in CO-OFDM/OQAM System

“…In addition, the performance of pilot aided methods relies on high power allocation of pilot symbol which may cause power degradation of effective signal. By contrast, blind methods are popularly used for PNE without additional SE loss [19,[24][25][26][27][28][29][30]. In [24], a blind phase search (BPS) with feedback loop (BPS-FL) was proposed for OFDM system.…”

“…Compared with BPS based methods, MEKF can only work under a low NLW with lower complexity. In [29], principal component analysis (PCA) method and PCA-BPS hybrid method were proposed to balance performance and complexity. Besides, Maximum likelihood (ML) based estimator and maximum a posteriori (MAP) based estimator were proposed in [19].…”