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Yayın A New speech coding algorithm using zero cross and phoneme based SYMPES(IEEE, 2013-07-11) Şişman, Burak; Güz, Ümit; Gürkan, Hakan; Yarman, Bekir Sıddık BinboğaIn this work, a new low bit rate hybrid speech coding approach which combines the benefits of the SYMPES (Systematic Procedure for Predefined Envelope and Signature Sequences) and zero cross and phoneme based segmentation is proposed. In the new approach, the SYMPES structure is developed in the phoneme based fashion. In order to achieve lower bit rates, some drawbacks such as computational complexity, relatively high encoding times etc. of the SYMPES are also eliminated in the new version. Experimental results show that in almost same bit rates very promising speech quality is obtained compared to the other conventional methods such as CELP (Code Excited Linear Predictive) coding algorithm.Yayın 2W wideband microwave PA design for 824-2170 MHz band using normalized gain function method(IEEE, 2013) Köprü, Ramazan; Kuntman, Hulusi Hakan; Yarman, Bekir Sıddık BinboğaIn this work, we present the design of a 2W linear wideband microwave PA (power amplifier) targeted to operate in 824-2170 MHz mobile frequency range covering GSM850, EGSM, DCS, PCS and WCDMA. The design is basically based on the NGF (Normalized Gain Function) method which is very recently introduced into the literature. NGF is defined as the ratio of T and |S-21|(2), i.e. T-NGF= T/|S-21|(2), shape of the gain function of the amplifier to be designed and the shape of the transistor forward gain function, respectively. Synthesis of input/output matching networks (IMN/OMN) of the amplifier requires target gain functions, which are mathematically generated in terms of TNGF. The particular transistor used in the design is FP31QF, a 2W HFET from TriQuint Semiconductor. Theoretical PA performance obtained in Matlab is shown to be in a very high agreement with the simulated performance in MWO (Microwave Office) of AWR Inc.Yayın Design of a broadband microwave amplifier constructed with mixed lumped and distributed elements for mobile communication(IEEE, 2002) Yarman, Bekir Sıddık Binboğa; Çimen, Ebru GürsuIn this paper, we designed a broadband microwave amplifier utilizing. the "semi-analytic method to describe symmetrical lossless two-ports with two-kinds of elements", namely, distributed and lumped elements in cascade connection. It is expected that the results presented in this paper will find immediate application to design analog/digital mobile communication systems put on MMICs or VLSI chips.Yayın Design and implementation of wideband microwave amplifiers based on Normalized Gain Function(Institute of Electrical and Electronics Engineers Inc., 2014) Köprü, Ramazan; Kılınç, Sedat; Aksen, Ahmet; Yarman, Bekir Sıddık BinboğaIn this work, we introduce the design and implementation of wideband microwave amplifiers based on "Normalized Gain Function (NGF)" method. Normalized Gain Function is defined as the ratio of desired shape or frequency response of the gain function of the amplifier to be designed and shape of the transistor forward gain function. Synthesis of input/output matching networks (IMN/OMN) of the amplifier require target gain curves as the functions of normalized gain function to be tracked in two sequential nonlinear optimization processes. A prototype low power amplifier circuit is produced and measured to show the usability of the design approach.Yayın Generation of optimum signature base sequences for speech signals(IEEE, 2000) Yarman, Bekir Sıddık Binboğa; Akdeniz, RafetIn our previous publications [1-6], we proposed a novel method to represent signals in terms of, so called, "Signature Base Functions-SBF' which were extracted from the physical features of the waveform under consideration. In [1-6], SBF were determined in ad-hoc manner, which requires tedious search process, and they were not orthogonal. Furthermore, optimality of SBF was in question. In this work however, we suggest a well-organised procedure to generate "Optimum Orthogonal Signature Base Functions-OSBF' for selected waveforms, which in turn provides excellent means for signal representations. II is shown that the new method of signal representation, which is based on OSBF, requires less computation time with substantial signal compression and results in efficient speaker dependent recognition.Yayın A tunable inductance topology to realize frequency tunable matching networks and amplifiers(IEEE, 2013) Atilla, Doğu Çağdaş; Aydın, Çağatay; Köprü, Ramazan; Nesimoğlu, Tayfun; Yarman, Bekir Sıddık BinboğaCoverage of commercial communication standards such as GSM, UMTS, Wi-Fi and Wi-Max within a single transceiver chip is one of the most desired properties by wireless communication manufacturers. In this regard, communication companies are keenly interested in the design of high power amplifiers for broadband cellular communications to achieve this coverage. In this work, design of broadband tunable matching networks is investigated using Real Frequency Techniques. In practical applications, tunability is needed to compensate for the load impedance variations with environmental effects. In order to be able to work on sample structures, impedance transforming filters with proper topology are chosen and a broadband tunable matching network with a tunability strategy is developed. Eventually a broadband amplifier has been designed using the tunable inductor concept.Yayın A novel computed tomography image compression method based on classified energy and pattern blocks(IEEE, 2013) Gökbay, İnci Zaim; Gezer, Murat; Güz, Ümit; Gürkan, Hakan; Yarman, Bekir Sıddık BinboğaIn this work, a new biomedical image compression method is proposed based on the classified energy and pattern blocks (CEPB). CEPB based compression method is specifically applied on the Computed Tomography (CT) images and the evaluation results are presented. Essentially, the CEPB is uniquely designed and structured codebook which is located on the both the transmitter and receiver part of a communication system in order to implement encoding and decoding processes. The encoding parameters are block scaling coefficient (BSC) and the index numbers of energy (IE) and pattern blocks (IP) determined for each block of the input images based on the CEPB. The evaluation results show that the newly proposed method provides considerable image compression ratios and image quality.Yayın Computer aided darlington synthesis of an all purpose immittance function(Istanbul University, 2016) Yarman, Bekir Sıddık Binboğa; Aksen, Ahmet; Köprü, Ramazan; Kumar, Narendra Senthil; Aydın, Çağatay; Atilla, Doğu Çağdaş; Chacko, PrakashThis work is the continuation of our high precision immittance synthesis paper series introduced in IEEE TCAS-I. In the present manuscript, we modified the previously introduced high precision Bandpass LC-ladder synthesis algorithm to include the extraction of finite frequency and right half plane (RHP) transmission zeros of an impedance function as Brune/Darlington Type-C sections. Finite frequency and RHP transmission zeros are extracted employing our newly introduced modified impedance and chain parameters based algorithms one by one. After each transmission zero extraction, remaining immittance function is corrected using parametric approach. It is shown that propsed high precision synthesis algorithms can synthesize immittance functions up to 40 reactive elements with accumulated relative error in the order of 10- 1 . The modified high precision synthesis package is developed in MatLab environment and it is integrated with the real frequency techniques to design matching networks over broadbands. Examples are presented to exhibit the usage of the newly proposed high precision synthesis algorithms.Yayın A single matching network design for a dual band PIFA antenna via simplified real frequency technique(2006-10) Lindberg, Peter; Şengül, Metin; Çimen, Ebru Gürsu; Yarman, Bekir Sıddık Binboğa; Rydberg, Anders; Aksen, AhmetIn this paper, the matched performance of a dual band PIFA antenna is reported. The return loss of the antenna has been optimized over the popular commercial wireless communication bands of 824-960 MHz and 1710-1990 MHz using only one matching network. The network was synthesized using the Simplified Real Frequency Technique, which yields an "easy to implement circuit topology" and realizable component values. With the implemented matching network, a simultaneous measured bandwidth enhancement of 58% and 127% has been achieved in the low and high frequency band, respectively, without significant reduction of radiation efficiency.Yayın Immitance data modelling via linear interpolation techniques(IEEE, 2002) Yarman, Bekir Sıddık Binboğa; Aksen, Ahmet; Kılınç, AliWith the advancement of the manufacturing technologies to produce new generation analog/digital communication systems, immitance data modelling has gained renewed importance in the literature. Specifically, models are utilised for behaviour characterisation, simulation of physical devices or to design sub-systems with active and passive solid-state components. Therefore, in this paper, new computer aided tools are presented to model one port immitance data by means of linear interpolation techniques. It is remarkable to observe that complex electrical behaviour of physical devices can be simulated with the models built utilising the linear interpolation of a few properly selected measured immitance data. An antenna example is presented to exhibit the implementation of the proposed techniques. It is expected that the new modelling tools will be employed to provide initial circuit topologies to the commercially available analysis/simulation and design packages.
