Blind channel estimation via combining autocorrelation and blind phase estimation

Symbol spaced blind channel estimation methods are presented which can essentially use the results of any existing blind equalization method to provide a blind channel estimate of the channel. Blind equalizer's task is reduced to only phase equalization (or identification) as the channel autocorrelation is used to obtain the amplitude response of the channel. Hence, when coupled with simple algorithms such as the constant modulus algorithm (CMA) these methods at baud rate processing provide alternatives to blind channel estimation algorithms that use explicit higher order statistics (HOS) or second-order statistics (subspace) based fractionally-spaced/multichannel algorithms. The proposed methods use finite impulse response (FIR) filter linear receiver equalizer or matched filter receiver based infinite impulse response+FIR linear cascade equalizer configurations to obtain blind channel estimates. It is shown that the utilization of channel autocorrelation information together with blind phase identification of the CMA is very effective to obtain blind channel estimation. The idea of combining estimated channel autocorrelation with blind phase estimation can further be extended to improve the HOS based blind channel estimators in a way that the quality of estimates are improved.


Blind matched filter receiver
Baykal, Buyurman (Institute of Electrical and Electronics Engineers (IEEE), 2004-02-01)
Matched filter receiver (MFR) of Forney in the presence of intersymbol interference (ISI) and additive white Gaussian noise is investigated from a blind perspective, which includes blind maximum likelihood sequence detection, blind decision feedback equalization and linear blind equalization. Various realizations of the blind MFR are discussed. In a blind MFR, the channel can be easily estimated using a simple algorithm such as the constant-modulus algorithm (CMA). In this sense, the CMA can be used to esti...
Optimum Nyquist filters with controlled time and frequency characteristics
Tuncer, Temel Engin (Institution of Engineering and Technology (IET), 2002-10-10)
A design procedure is presented for pulse shaping filters based on the eigenfilter method. This method presents great flexibility for the control of the tail decay and stopband attenuation of the pulse shaping filters. A variety of optimum filters can be designed which are better than raised cosine filters both in time and frequency.
Joint spatial and temporal channel-shortening techniques for frequency selective fading MIMO channels
Toker, Canan; Chambers, JA; Baykal, Buyurman (2005-02-01)
It is well understood that the maximum likelihood estimator is a powerful equalisation technique for frequency selective fading channels, and in particular for MIMO systems. The complexity of this estimator, however, grows exponentially with the number of users and multipath taps, hence limiting the use of this algorithm in MIMO systems. In the paper, the authors propose a joint spatial and temporal channel-shortening filter as a pre-processor to reduce significantly the complexity of a maximum likelihood e...
Triple stub circuit topology as simultaneous insertion phase, amplitude and impedance control circuit for phased array applications
Unlu, M.; Demir, Şimşek; Akın, Tayfun (Institution of Engineering and Technology (IET), 2012-10-23)
This study shows that the well-known triple stub circuit topology can also be used for controlling the insertion phase and amplitude of a given signal simultaneously, as well as preserving its impedance transformation ability. The triple stub circuit topology, which is nothing but an extension of the conventional double stub loaded-line phase shifter, results in one more degree of freedom to its solution when it is solved for its insertion phase. This additional degree of freedom not only brings the impedan...
Dynamic range enhancements in radio receivers by means of frequency retranslation
Nesimoglu, T.; Charalampopoulos, Z.; Warr, P. A.; Beach, M. A. (Institution of Engineering and Technology (IET), 2012-03-20)
In this study, a receiver architecture is presented that may be used for linearisation or for large signal interference suppression. In linearisation mode, an error signal that consists of intermodulation distortion products is obtained and used for predistorting the receiver. Experimental results demonstrate > 16 dB improvement of third-order input intercept point when used in a superheterodyne topology. When used in a direct conversion receiver topology, 7-dB improvement of second-order input intercept po...
Citation Formats
B. Baykal, “Blind channel estimation via combining autocorrelation and blind phase estimation,” IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS, pp. 1125–1131, 2004, Accessed: 00, 2020. [Online]. Available: