High frequency communication experiments between the UK and Turkey

Erol, Berin Cemil


An Investigation on belief propagation decoding of polar codes
Doğan, Orkun; Diker Yücel, Melek; Department of Electrical and Electronics Engineering (2015)
Polar codes are provably symmetric capacity achieving codes for any given binary input discrete memoryless channel, with low encoding and decoding complexities. Polar codes introduced by Erdal Arıkan in 2009 are based on the channel polarization. N binary channels are synthesized out of N copies of binary input discrete memoryless channels, such that as N goes to infinity each of the synthesized channel’s capacity goes to either 0 or 1; i.e., the channels are seen purely as noisy or noiseless channels. Thes...
A Comparison of sparse signal recovery and approximate bayesian inference methods for sparse channel estimation
Uçar, Ayla; Candan, Çağatay; Department of Electrical and Electronics Engineering (2015)
The concept of sparse representation is one of the central methodologies of modern signal processing and it has had significant impact on numerous application fields such as communications and imaging. Sparsity expresses the idea that the information rate of a continuous time signal may be much smaller than suggested by its bandwidth, or that a discrete time signal depends on a number of degrees of freedom which is comparably much smaller than its (finite) length. With recent advances in sparse signal estim...
A Novel Adaptive Pre Screener For Ground Penetrating Radar
Baydar, Bora; Akar, Gözde (2016-05-19)
This paper describes a novel pre-screener algorithm for landmine detection with a ground penetrating radar (GPR). The pre-screener algorithms are used for finding anomalies that are potential locations of interest. Thus, their processing time is as important as their true detection rate and false alarm rate. The proposed approach is based on Kernel Least Mean Square algorithm. Although Least Mean Square (LMS) based approach has already been used in the literature, KLMS based approach is a novel application ...
Propagation models for hilly terrain based on ray optic methods
Yıldırım, Erkan Ersin; Dural Ünver, Mevlüde Gülbin; Department of Electrical and Electronics Engineering (2015)
In RF propagation path loss modeling, numerical methods may not be useful since they require very long computation times because electrically very large objects may be located in the terrain. Ray optic methods such as Geometrical Optics (GO) or Geometrical Theory of Diffraction (GTD) are more commonly used in propagation problems as well as the empirical models. Although ray optics methods are designed for very high frequency applications, they provide quite accurate path loss estimations in hilly terrain i...
Opportunistic multiple relaying in wireless ad hoc networks
Yenihayat, Güven; Yılmaz, Ali Özgür; Department of Electrical and Electronics Engineering (2011)
Cooperative relaying systems aim to improve weak communication links by exploiting the spatial diversity obtained by the statistically independent channels between relays and the destination. In this thesis a cooperative relaying scheme called the Opportunistic Multiple Relaying (OMR) is proposed with its special receiver structure. Unlike most relaying schemes in the literature, multiple relay nodes are allowed to transmit in nonorthogonal channels in OMR without requiring any control overhead for relay co...
Citation Formats
B. C. Erol, “High frequency communication experiments between the UK and Turkey,” Ph.D. - Doctoral Program, Middle East Technical University, 1996.