Low-Complexity Iterative Channel Estimation and Tracking for Time-Varying Multi-Antenna Systems

Download
2009-09-16
Yapici, Yavuz
Yılmaz, Ayşen
The iterative channel estimation and tracking problem is considered for time-varying frequency-flat fading multiinput multi-output (MIMO) systems. In order to jointly estimate and track the time-varying multi-antenna channel, the pilot symbol assisted modulation (PSAM) technique is generalized to the multi-antenna systems. By distributing the pilot symbols along the transmitted block, i.e., PSAM transmission, the proposed system gains the ability to track the channel variation with the same amount of pilots whereas the system with all the pilots are employed prior to the data block has no tracking capability. The error performance is further improved by iteratively estimating the channel which employs the optimal MMSE filtering and also makes use of the soft probabilities of the coded symbols provided by the decoder. In order to decrease the computational complexity due to the iterative usage of MMSE filtering, we introduce the low-complexity 2-way LMS algorithm based on the forward-backward operation of conventional forward only LMS algorithm. By simulations, 2-way LMS is shown to have a near optimal error performance and highly better channel tracking ability than the conventional LMS algorithm with no significant complexity increase.
20th IEEE Symposium on Personal, Indoor and Mobile Radio Communications

Suggestions

Improvements in DOA estimation by array interpolation in non-uniform linear arrays
Yaşar, Temel Kaya; Tuncer, Temel Engin; Department of Electrical and Electronics Engineering (2006)
In this thesis a new approach is proposed for non-uniform linear arrays (NLA) which employs conventional subspace methods to improve the direction of arrival (DOA) estimation performance. Uniform linear arrays (ULA) are composed of evenly spaced sensor elements located on a straight line. ULA's covariance matrix have a Vandermonde matrix structure, which is required by fast subspace DOA estimation algorithms. NLA differ from ULA only by some missing sensor elements. These missing elements cause some gaps in...
Effect of water-filling method on the PAPR for OFDM and MIMO systems
Vural, Mehmet; Akta, Tugcan; Yılmaz, Ali Özgür (2007-06-13)
In this paper, the peak-to-average power ratio (PAPR) problem for orthogonal frequency division multiplexing (OFDM) is investigated. The variations in the nature of the problem along with the utilization of water-filling technique are observed and the corresponding cumulative distribution function for PAPR is determined. In addition to OFDM analysis, another analysis is carried out for the comparison of water-filling technique and an equal power distribution algorithm in case of a multiple input multiple ou...
Improvements to neural network based restoration in optical networks
Türk, Fethi; Bilgen, Semih; Department of Electrical and Electronics Engineering (2008)
Performance of neural network based restoration of optical networks is evaluated and a few possible improvements are proposed. Neural network based restoration is simulated with optical link capacities assigned by a new method. Two new improvement methods are developed to reduce the neural network size and the restoration time of severed optical connections. Cycle based restoration is suggested, which reduces the neural network structure by restoring the severed connections for each optical node, iterativel...
Radar pulse repetition interval tracking with kalman filter
Avcu, Soner; Demirbaş, Kerim; Department of Electrical and Electronics Engineering (2006)
In this thesis, the radar pulse repetition interval (PRI) tracking with Kalman Filter problem is investigated. The most common types of PRIs are constant PRI, step (jittered) PRI, staggered PRI, sinusoidally modulated PRI. This thesis considers the step (this type of PRI agility is called as constant PRI when the jitter on PRI values is eliminated) and staggered PRI cases. Different algorithms have been developed for tracking step and staggered PRIs cases. Some useful simplifications are obtained in the alg...
Multitarget tracking performance metric: deficiency aware subpattern assignment
Oksuz, Kemal; CEMGİL, ALİ TAYLAN (2018-03-01)
Multitarget tracking is a sequential estimation problem where conditioned on noisy sensor measurements, state variables of several targets need to be estimated recursively. In this study, the authors propose a novel performance measure for multitarget tracking named as Deficiency Aware Subpattern Assignment (DASA), that can be used to consistently compare algorithms in a broad spectrum of formulations ranging from conventional data association methods to random finite set based multitarget tracking algorith...
Citation Formats
Y. Yapici and A. Yılmaz, “Low-Complexity Iterative Channel Estimation and Tracking for Time-Varying Multi-Antenna Systems,” presented at the 20th IEEE Symposium on Personal, Indoor and Mobile Radio Communications, Tokyo, JAPAN, 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/32495.