Pseudo-Pilot Coding Based Phase Noise Estimation for Coherent Optical FBMC-OQAM Transmissions

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

“…Normally, PNE schemes can be classified into two categories according to the usage of pilot or not: pilot-aided methods and blind estimation methods. Pilot-aided methods often insert known pilot symbols into transmitted symbols to record PN [20][21][22][23]. For example, a PN suppression method based on orthogonal basis expansion was proposed for wireless system in [20] which supported reliable PNE at the cost of 7.3% Spectral efficiency (SE) loss.…”

“…For example, a PN suppression method based on orthogonal basis expansion was proposed for wireless system in [20] which supported reliable PNE at the cost of 7.3% Spectral efficiency (SE) loss. In [21], a pseudo-pilot coding based phase estimation method was proposed for coherent optical FBMC system, achieving a reliable performance at the cost of 3.1% SE loss. In [22], a pilot-based extended Kalman filter (PEKF) was proposed for coherent optical FBMC system and achieved 1.2×10 -2 normalized linewidth (NLW) tolerance with 2.34% SE loss.…”

“…In [23], a special pseudo pilot structure was proposed for FBMC system with lower SE loss of 1.2%. The pilot aided methods in [20][21][22][23] all cause SE loss because of pilot symbol insertion. In addition, the performance of pilot aided methods relies on high power allocation of pilot symbol which may cause power degradation of effective signal.…”

Time-Domain Blind ICI Compensation in Coherent Optical FBMC/OQAM System

“…Due to the nonorthogonality in imaginary plane, the PNC and channel estimation techniques are severely restricted by the so-called intrinsic imaginary interference (IMI) in CO-FBMC/OQAM systems [19][20][21][22][23][24]. Consequently, many studies on the PNC method focus on the IMI cancellation [25][26][27]. In [26], a pilot-based PNC method is used to suppress the IMI at the expense of SE, where a pilot structure consists of several additional data symbols surrounding a pilot symbol.…”

“…In [26], a pilot-based PNC method is used to suppress the IMI at the expense of SE, where a pilot structure consists of several additional data symbols surrounding a pilot symbol. Another alternative approach is a coding scheme, and data symbols surrounding a pilot are deliberately coded to eliminate the IMI in that pilot [26,27]. Although the complexity of two mainly pilot-based PNC methods is moderate, their performance is limited by only CPE compensation.…”