Source: https://www.radioeng.cz/papers/2015-4.htm
Timestamp: 2019-04-23 06:17:09+00:00

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In this paper, a microwave sensor based on an artificial transmission line is proposed for non-invasive blood glucose monitoring. A corresponding numerical model of the sensor implemented in microstrip technology is created in the commercial full-wave numerical simulation tool COMSOL Multiphysics and virtually tested by means of numerical simulations. Blood-glucose solution models with various blood glucose concentrations are used as a model of a biological tissue under test. Furthermore, a possible methodology for performing non-invasive tests is proposed. Sensitivity of the sensor developed here is compared to a sensor based on a section of a conventional microstrip transmission line of the same length and width.
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GREEN, E. C. Design of a Microwave Sensor for Non-Invasive Determination of Blood-Glucose Concentration. Ph.D. Thesis, 2005.
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VRBA, D., VRBA, J., RODRIGUES, D., STAUFFER, P. Numerical investigation of novel microwave applicators based on zero-order mode resonance for hyperthermia treatment of cancer. Journal of The Franklin Institute, 2015. Accepted for publication. ISSN: 0016-0032.
We report about three branch large core polymer power splitters optimized for connecting standard plastic optical fibers. A new point of the design is insertion of a rectangle-shaped spacing between the input and the central part of the splitter, which will ensure more even distribution of the output optical power. The splitters were designed by beam propagation method using BeamPROP software. Acrylic-based polymers were used as optical waveguides being poured into the Y-grooves realized by computer numerical controlled engraving on poly(methyl methacrylate) substrate. Measurement of the optical insertion losses proved that the insertion optical loss could be lowered to 2.1 dB at 650 nm and optical power coupling ratio could reach 31.8% : 37.3% : 30.9%.
SAKAI, A., FUKAZAWA, T., TOSHIHIKO, B. Low loss ultra small branches in silicon photonic wire waveguide. IEICE Transactions on Electronics, 2002, vol. E85-C, no. 4, p. 1033 to 1038. ISSN: 1745-1353.
BETTIOL, A. A., SUM, T. C., CHEONG, F. C., SOW, C. H., RAO, S. V., van KAN, J. A., TEO, E. J., ANSARI, K., WATT, F. A progress review of proton beam writing applications in microphotonics. Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms, 2005, vol. 231, p. 364–371. ISSN: 0168-583X.
Measurements of test antennas are performed on antenna ranges. The operated microwave far-field outdoor range was built-up in 1970’s and therefore it was not appropriate for the today measurements. Thus, it was decided to perform the complete reconstruction and testing. Some results of new ample measurement campaign are just given. The optimization of antenna range using merely measurement is very inefficient, and therefore that is done by numerical simulations. Consequently the paper surveys briefly electromagnetic wave propagation over irregular terrain. The physical optics approximation of vector problem was chosen. That allows the comparison of selected numerical simulations and measurements for the reconstructed far-field range. A possibility of antenna range optimizing by using numerical simulation considering various constraints is verified.
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SMITH, D., YURDUSEVEN, O., LIVINGSTONE, B., SCHEJBAL, V. Microwave imaging using indirect holographic techniques. IEEE Antennas and Propagation Magazine, Feb 2014, vol. 56, no. 1, p. 104–117. DOI: 10.1109/MAP.2014.6821762.
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SCHEJBAL, V., FISER, O. Enhanced analysis of propagation over irregular terrain In EuCAP 2010. Barcelona (Spain), 2010, p. 1697-1701. ISBN 978-1-4244-6431-9.
UFIMTSEV, P. Ya. Improved physical theory of diffraction: removal of the grazing singularity. IEEE Transactions on Antennas and Propagation, Oct 2006, vol. 54, no. 10, p. 2698–2702. DOI: 10.1109/TAP.2006.882179.
ZAVODNY, V., KOPECKY, P. Reflector antenna in L band. In Conference on Microwave Techniques (COMITE). Pardubice (Czech Republic), 22-23 April 2015, p. 68–71. DOI: 10.1109/COMITE.2015.7120337.
ZAVODNY, V., KOPECKY, P. Measurement of far-field patterns of phased array antennas. In Conference on Microwavwe Techniques (COMITE). Pardubice (Czech Republic), 22-23 April 2015, p. 72–74. DOI: 10.1109/COMITE.2015.7120333.
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Keywords: Microwave antenna, antenna measurements, irregular surface, physical optics, numerical analysis, experiments.
We designed a patch antenna surrounded by a mushroom-like electromagnetic band-gap (EBG) structure and completed it by a partially reflective surface (PRS). EBG suppresses surface waves and creates the bottom wall of the Fabry-Perot (FP) resonator. PRS plays the role of a planar lens and forms the top wall of the FP resonator. The novel PRS consists of a two-layer grid exhibiting inductive and capacitive (LC) behavior which allows us to obtain a reflection phase between –108 and +180 degrees. Thanks to this PRS, we can control the height of the cavity in the range from λ/2 to λ/300. Obtained results show that the FP resonator antenna enables us to achieve a low profile and a high-gain. The patch is excited by a microstrip transmission line via the cross-slot aperture generating the circular polarization. Functionality of the described concept of the FP antenna was verified at 10 GHz. The antenna gain was 15 dBi, the impedance bandwidth 2.3% for |S11| < –10 dB, and the axial ratio bandwidth 0.6% for AR < 3.0 dB. Hence, the antenna is suitable for narrowband applications. Computer simulations show that the microwave FP antenna can be simply redesigned to serve as a source of circularly polarized terahertz waves.
Six-port reflectometer is well-known for its ability to measure magnitude and phase-shift of microwave signal using four power detectors that perform magnitude-only measurements. This paper presents the development of an innovative symmetric ring junction as four-port reflectometer for complex reflection coefficient measurements. It reduces the number of required detectors to two. Design optimization, new calibration modeling and algorithm are discussed in details for this four-port reflectometer. The developed four-port reflectometer is compared to five-port reflectometer and vector network analyzer. It is found that the measured magnitude and phase-shift shows good performance in comparison with the commercial vector network analyzer and the five-port reflectometer.
TRUSHKIN, A. N. A measuring device of the complex reflection coefficient. In IEEE 23rd International Crimean Conference Microwave and Telecommunication Technology (CriMiCo). Sevastopol (Ukraine), 2013, p. 963–964.
BILIK, V. Six-port measurement technique: Principles, impact, applications. In Proceedings of the International Conference Radioelektronika. 2002.
A wideband I-type rectangular waveguide rotary joint (RJ) is designed, simulated and built. It has an excellent performance over the whole Ku Band (10.7-14.5 GHz) where the return loss is less than -23 dB at its highest and the insertion loss is below 0.4 dB. The rotary joint is specifically designed for satellite news gathering (SNG) vehicles providing elevation and azimuthal movement to the antenna and matching polarization when it is needed at the feed. It can also be used in other high power microwave applications,where rotation ability of the antenna is a must during the transmission such as radars.
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MALLAHZADEH, A., AHMADABADI, H. Design of N-channel rotary joint using curved double ridged waveguide and concentric coaxial lines. Applied Computational Electromagnetics Society Journal, 2012, vol. 27, no. 1, p. 50–58.
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BOSTAN, S. M. KU Band Waveguide Component Design for SNG Vehicles. MSc Thesis. Istanbul (Turkey): Yıldız Technical University, 2011.
Time and frequency synchronization is the key technique of bistatic synthetic aperture radar (BiSAR) system, and raw data simulation is an effective tool for verifying the time and frequency synchronization techniques. According to the two-dimensional (2-D) frequency spectrum of fixed-receiver BiSAR with time and frequency synchronization errors, a rapid raw data simulation method is proposed in this paper. Through 2-D inverse Stolt transform in 2-D frequency domain and phase compensation in Range-Doppler frequency domain, this method can realize two-dimensional spatial variation simulation for fixed-receiver BiSAR with time and frequency synchronization errors in a reasonable time consumption. Then the simulation efficiency of scene raw data can be significantly improved. Simulation results of point targets and extended scene are presented to validate the feasibility and efficiency of the proposed simulation method.
In this paper, an analysis method of wideband loaded-stub phase shifters and a fast designing procedure is presented. These kinds of phase shifters use a transmission line loaded with one or two open stubs and a reference line to achieve up to 135° phase shift. Analysis results shows that lower than -10dB return loss and precise phase shift can be achieved over a 100% bandwidth employing the ideal open stubs. To approach the ideal impedance value of the open stubs, an arrow-shaped stub and several means to control its impedance is proposed. As verification of the analysis method, a 90° two-stub loaded phase shifter is easily designed and fabricated. Measured results show the design achieves better than ±4° phase ripple, less than 0.5dB insertion loss, and better than 10dB return loss over an 85% wideband.
Ultra wideband (UWB) automotive radars have attracted attention from the viewpoint of reducing traffic accidents. The performance of automotive radars may be degraded by interference from nearby radars using the same frequency. In this study, a scenario where two cars pass each other on a road was considered. Considering the utilization of cross-polarization, the desired-to-undesired signal power ratio (DUR) was found to vary approximately from -10 to 30 dB. Different pseudo random sequences were employed for spectrum spreading the different radar signals to mitigate the interference effects. This paper evaluates the interference suppression provided by maximum length sequence (MLS) and Gold sequence (GS) through numerical simulations of the radar’s performance in terms of probability of false alarm and probability of detection. It was found that MLS and GS yielded nearly the same performance when the DUR is -10 dB (worst case); for example when fixing the probability of false alarm to 0.0001, the probabilities of detection were 0.964 and 0.946 respectively. The GS are more advantageous than MLS due to larger number of different sequences having the same length in GS than in MLS.
The Fractional Frequency Reuse (FFR) is a resource allocation technique that can effectively mitigate inter-cell interference (ICI) in LTE based HetNets and it is a promising solution. Various FFR schemes have been suggested to address the challenge of interference in femtocell systems. In this paper, we study the scopes of interference mitigation and capacity improvement. We propose a resource allocation scheme that gradually varies frequency resource share with distance from the eNodeB for both macrocells and femtocells in order to attain better utilization of the resources. This is performed effectively using three layers in the cell. The proposal also employs high number sectors in a cell, low interference and good frequency reuse. Monte-Carlo simulations are performed, which show that the proposed scheme achieves significantly better throughput compared to the existing FFR schemes.
3GPP, R1-050507, Huawei. Soft frequency reuse scheme for LTE, 2005.
In this paper, full rate space-time-frequency coding applied to orthogonal frequency division multiplexing based power line communication systems. The proposed systems yield both time and frequency diversity and keep transmission rate full. Performances of the systems are evaluated for three conductors of low voltage indoor cables and are compared with space-frequency and space-time-frequency coding applied power line communication systems in the literature. Owing to the higher order diversity level the proposed full rate space-time-frequency systems have an increasing advantage over space-frequency systems as the SNR level above 12.5dB. On the other hand owing to transmission rate advantage the proposed full rate space-time-frequency systems can have more than 6dB gain over the other space-time-frequency coding applied power line communication systems in the literature.
This paper presents a novel diversity receiver of MPSK signal in fading channel in the presence of the carrier frequency offset. As a part of this receiver, a new algorithm for the estimation of the combining coefficients (ECC algorithm) is introduced. Having in mind that the QPSK modulation is one of the most used modulation formats in many wireless communication standards (LTE, WiFi, WiMax), the performance of the proposed receiver is analyzed in more detail for the QPSK modulation. In the presence of Rayleigh fading, representing the most severe fading condition, this algorithm shows significantly better performance comparing to the same receiver structure that uses conventional constant modulus algorithm (CMA1 or CMA2). The proposed diversity receiver structure with ECC algorithm operates within a wide carrier frequency offset range with a very small variation of the performance. For this reason, it can be applied in 4G mobile communication systems.
PROAKIS, J. G. Digital Communications. 4th ed., New York (USA): McGraw-Hill, 2001. ISBN: 0072321113.
DIMITRIJEVIĆ, B. R., MILOSEVIĆ, N., MARSALEK, R., NIKOLIĆ, Z. B. BPSK receiver based on recursive adaptive filter with remodulation. Radioengineering, vol. 20, no. 4, 2011, p. 932 to 936, ISSN: 1210-2512.
NWALOZIE, C., OKOROGU, N., UMEH, C., ORAETUE, D. Performance analysis of constant modulus algorithm (CMA) blind adaptive algorithm for smart antennas in a W-CDMA network. International Journal of Engineering Science and Innovative Technology, 2012, vol. 1, no. 2, p. 246–254. ISSN: 2319-5967.
The hysteresis loops pinched in the v-i origin belong to well-known fingerprints of memristive elements driven by bipolar periodical signals. Some element properties follow from the loop behavior in the close neighborhood of the origin. The paper analyzes this behavior of the memristive elements that produce steady-state hysteresis loops under harmonic excitation. It is shown that there is a connection between the frequency content of the state variable waveform and the type of the loop being pinched.
BIOLEK, Z., BIOLEK, D., VAVRA, J., BIOLKOVA, V., KOLKA, Z. The simplest memristor in the world. Submitted to International Conference on Circuits and Systems (ISCAS 2016). Montreal (Canada), 2016.
Recently, many reactance-less memristive relaxation oscillators were introduced, where the charging and discharging processes depend on memristors. In this paper, we investigate the power dissipation in different memristor based relaxation oscillators. General expressions for these memristive circuits as well as the power dissipation formulas for three different topologies are derived analytically. In addition, general expressions for the maximum and minimum power dissipation are calculated. Finally, the calculated expressions are verified using PSPICE simulations showing very good matching.
FOUDA, M., RADWAN, A. simple floating voltage-controlled memductor emulator for analog applications. Radioengineering, 2014, vol. 23, no. 3., p. 944–948.
BIOLEK, Z., BIOLEK, D., BIOLKOVA, V. SPICE model of memristor with nonlinear dopant drift. Radioengineering, 2009, vol. 18, no. 2, p. 210–214.
PERSHIN, Y. V., DI VENTRA, M. SPICE model of memristive devices with threshold. Radioengineering, 2013, vol. 22, no. 2., p. 485–489.
BIOLEK, D., DI VENTRA, M., PERSHIN, Y. Reliable SPICE simulations of memristors, memcapacitors and meminductors. Radioengineering, 2013, vol. 22 , no. 4, p. 945–968.
Keywords: Memristor, power, reactance-less, memristive circuits, oscillators.
This paper describes the design of current mode low-pass ladder filters based on CMOS technology. The filters are derived from passive RLC ladder filter prototypes using new CMOS lossy and lossless integrators. The all-pole and Elliptic approximations are used in the proposed low-pass filter realizations. The proposed two types of filter can be electronically tuned between 10kHz and 100MHz through bias current from 0.03µA to 300µA. The proposed filters use 1.5 V power supply with 3 mW power consumption at 300 µA bias current. The proposed filters are resistorless, use grounded capacitors and are suitable for further integration. The total harmonic distortion (THD) of the low-pass filters is less than 1% over the operating frequency range. PSPICE simulation results, obtained by using TSMC 0.18µm technology, confirm the presented theory.
Current sensor is an integral part of every switching converter. It is used for over-current protection, regulation and in case of multiphase converters for balancing. A new high voltage current sensor for coil-based current sensing in DC-DC converters is presented. The sensor employs DDCC with high voltage input stage and gain trimming. The circuit has been simulated and implemented in 0.35 um BCD technology as part of a multiphase DC-DC converter where its function has been verified. The circuit is able to sustain common mode voltage on the input up to 40 V, it occupies 0.387*0.345 mm2 and consumes 3.2 mW typically.
WICHT, B., KULHARNI, S. P., HERZER, S., NEIDHARDT, J. Switched Mode Power Supply with Current Sensing, US Patent 8,203,323. June 19, 2012.
In this paper, a new architecture for efficient linear radio frequency transmitters is proposed; it includes envelope-tracking (ET) and envelope-elimination-and-restoration (EER) architectures as special instances. The proposed technique is referred to as Envelope Factorization with Partial Elimination and Recombination (EF-PER). It relies on a decomposition of the RF signal before power amplification as a product of two signals, one of them being the envelope signal elevated to an exponent “α”. Compared to ET or EER architectures, the parameter “α” constitutes a new degree of freedom. This allows one to realize good tradeoffs between different performance criteria such as spectrum use, power efficiency, and transmitter linearity. An intuitive aggregate cost function is introduced to capture the desired tradeoff and turns out to be maximized in α=0.5. The full relevance of EF-PER is sustained both by analytical results and realistic simulations performed for OFDM signals. The EF-PER architecture (with α=0.5) has been simulated under Agilent-ADS with a non-linear transistor model from Avago (E-PHEMT) and compared with ET and EER.
Handset PA Linearization using Envelope Tracking. Nujira white paper. http://www.nujira.com.
CIDRONALI, A., MANES, G., GIOVANNELLI, N., VLASITS, T., HERNAMAN, R. Efficiency and linearity enhancements with envelope shaping control in dual-band envelope tracking GaAs PA. In Proceedings of the European Microwave Integrated Circuits Conference. Manchestr (UK), 2011, p. 308–311.
Keywords: EER, ET, linearization techniques, power efficiency, PAPR, RF architecture, RF linear transmitter.
This paper proposes a new method for designing the polynomial-interpolation-type noninteger-delay filter with a new structure formulation. Since the design formulation and the new realization structure are based on the discrete Pascal transform (DPT) and Pascal interpolation, we call the resulting filter Pascal noninteger-delay filter. The kth-order Pascal polynomial is used to pass through the given (k+1) data points in achieving the kth-order Pascal filter. The Pascal noninteger-delay filter is a real-time filter that consists of two sections, which can be realized into the front-section and the back-section. The front-section contains multiplication-free digital filters, and the number of multiplications in the back-section just linearly increases as order becomes high. Since the new Pascal filter has low complexity and structure can adjust non-integer delay online, it is more suited for fast delay tuning. Consequently, the polynomial-interpolation-type delay filter can be achieved by using the Pascal approach with high efficiency and low-complexity structure.
DENG, T.-B. High-resolution image interpolation using twodimensional Lagrange-type variable fractional-delay filter. In Proceedings of International Symposium on Nonlinear Theory and Applications (NOLTA 2005). Bruges (Belgium), 2005, p. 214–217.
Keywords: Low-complexity filter structure, noninteger-delay filter, discrete Pascal transform (DPT), polynomial-interpolation-type delay filter, Pascal noninteger-delay filter.
A novel quasi-coherent noise jamming method is proposed against linear frequency modulation (LFM) signal and pulse compression radar. Based on the structure of digital radio frequency memory (DRFM), the jamming signal is acquired by the pseudo-random sequence phase-modulation of sampled radar signal. The characteristic of jamming signal in time domain and frequency domain is analyzed in detail. Results of ambiguity function indicate that the blanket jamming effect along the range direction will be formed when jamming signal passes through the matched filter. By flexible controlling the parameters of interrupted-sampling pulse and pseudo-random sequence, different covering distances and jamming effects will be achieved. When the jamming power is equivalent, this jamming obtains higher process gain compared with non-coherent jamming. The jamming signal enhances the detection threshold and the real target avoids being detected. Simulation results and circuit engineering implementation validate that the jamming signal covers real target effectively.
Internet has affected our everyday life drastically. Expansive volumes of information are exchanged over the Internet consistently which causes numerous security concerns. Issues like content identification, document and image security, audience measurement, ownership, copyrights and others can be settled by using digital watermarking. In this work, robust and imperceptible non-blind color image watermarking algorithm is proposed, which benefit from the fact that watermark can be hidden in different color channel which results into further robustness of the proposed technique to attacks. Given method uses some algorithms such as entropy, discrete wavelet transform, Chirp z-transform, orthogonal-triangular decomposition and Singular value decomposition in order to embed the watermark in a color image. Many experiments are performed using well-known signal processing attacks such as histogram equalization, adding noise and compression. Experimental results show that proposed scheme is imperceptible and robust against common signal processing attacks.
RIDZOŃ, R., LEVICKY, D. Robust digital watermarking based on the log-polar mapping. Radioengineering, 2007, vol. 16, no. 4, p. 76–81.
GHAFOOR, A., IMRAN, M. A non-blind color image watermarking scheme resistant against geometric attacks. Radioengineering, 2012, vol. 21, no. 4, p. 1246–1251.
LEVICKY, D., FORIS, P. Human visual system models in digital image watermarking. Radioengineering, 2004, vol. 13, no. 4, p. 38–43.
KIM, T.-H., ADELI, H. Advances in Computer Science and Information Technology. Berlin Heidelberg: Springer, 2010. ISSN: 0302-9743.
KEKRT, D., LUKES, T., KLIMA, M., FLIEGEL, K. 2D iterative MAP detection: Principles and applications in image restoration. Radioengineering, 2014, vol. 23, no. 2, p. 618–631.
ZUKAL, M., MEKYSKA, J., CIKA, P., SMEKAL, Z. Interest points as a focus measure in multi-spectral imaging. Radioengineering, 2013, vol. 22, no. 1, p. 68–81.
SINGH CHANDEL, G., KUMAR, R., KHARE, D., VERMA, S. Analysis of image segmentation algorithms using MATLAB. International Journal of Engineering Innovation & Research, 2012, vol. 1, p. 51–55. ISSN 2277 – 5668.
LUKAC, R., PLATANIOTIS, N. K. Color Image Processing: Methods and Applications. USA: Taylor & Francis Group, 2007. ISBN: 978-0-8493-9774-5.
Unmanned Aerial Vehicles (UAV) will increasingly be used for responding to emergencies or for law enforcement in civil surveillance applications. Transferring the enormous amounts of information from UAV-mounted cameras or sensors will require large bandwidths, unlike the information required for remotely controlling a UAV, thus necessitating higher frequency bands typically in the vicinity of 2 or 5 GHz. Novel hardware developments will need to rely on a versatile propagation channel model for the envisaged scenarios ranging from deep shadow urban areas to open fields. This paper studies more complex intermediate scenarios, which fall between the aforementioned ones, and which are more difficult to model. A semi-deterministic model, first developed for open, flat areas, has been generalized to accommodate any possible operational scenario and was tested in built-up areas. The model involves a stochastic part and a determinist which is a ray-tracing based part used to compute the long term mean (LTM) of the signal's coherent component.
BARSOCCHI, P. Channel models for terrestrial wireless communications: a survey. CNR-ISTI Technical Report, April 2006.
ZELENY, J., PEREZ-FONTAN, F., PECHAC, P., MARINOESPINEIRA, P. Open area 2×2 MIMO channel model for 2GHz low elevation links with diversity and capacity applications. IEEE Transactions on Antennas and Propagation (submitted).
ZELENY, J., PEREZ-FONTAN, F., PECHAC, P. Initial results from a measurement campaign for low elevation angle links in different environments. In Proceedings of the 9-th European Conference on Antennas and Propagation (EuCAP). Lisbon (Portugal), April 2015, 4 p.
LACOSTE, F., CARVALHO, F., PEREZ-FONTAN, F., NUNEZFERNANDEZ, A., FABBRO, V., SCOT, G. MISO and SIMO measurements of the Land Mobile Satellite propagation channel at S-band. In Proceedings of the 4th European Conference on Antennas and Propagation (EuCAP). Barcelona (Spain), 2010, 5 p.
In this study the authors provide a cross-layer design of multiple-input-multiple-output (MIMO) systems, with the aim to maximize spectral efficiency. We consider MIMO systems based on a multichannel beamforming technique that combines an adaptive modulation and truncated automatic repeat request procedures, for the case of Rayleigh fading propagation and imperfect channel state information. Closed-form expressions for the average spectral efficiency and the packet loss rate are derived for arbitrary eigenchannel of multichannel beamforming systems, with any number of receiving and transmitting antennas. An analytical expression for the average time during which a particular constellation is used continuously, is also derived. We propose the method based on the optimization of the target packet error rate and the maximum number of retransmissions that outperforms the existing cross-layer combining procedures. Furthermore, we develop the numerical algorithm for optimization of the eigenchannel power allocation. The proposed cross-layer design results in higher average spectral efficiency, reduced maximum delay and increased energy efficiency. The analytical results are validated by Monte Carlo simulation.
NIKOLIC, B., DIMITRIJEVIC, B., MILOSEVIC, N., DJORDEVIC, G. T. Performance improvement of QPSK signal predetection EGC diversity receiver. Radioengineering, 2012, vol. 21, no. 3, p. 831–837.
YU, X., LIU, Y., LI, Y. ZHU, Q., YIN X., QIAN, K. Performance of cross-layer design with multiple outdated estimates in multiuser MIMO system. Radioengineering, 2014, vol. 23, no. 3, p. 863–871.
This paper deals with DRM (Digital Radio Mondiale) Plus and FM (Frequency Modulation) radio broadcasting systems coexistence. It brings results based on measurement of mutual interferences of each to other. Minimal necessary value of the signal to interference power ratio is measured under the given reception criteria. Results are useful for broadcasting networks planning. Different DRM Plus modes (i.e. combinations of various protection levels and data carriers modulations) are assumed in the case of DRM Plus reception interfered with by FM broadcasting. The differences for various modes are crucial for coverage design of DRM Plus system, while protection ratios have been recommended for only two of eight modes until now. Corrections of protection ratios for other modes are proposed in this paper. Different waveforms types of modulating signal for interfering FM signal are tested. The both mono and stereo FM mode and various sound quality criteria are considered in the case of FM broadcasting reception interfered with by DRM Plus. The influence of peak to average power ratio reduction of interfering DRM Plus signal is observed.
STEIL, A., KREUTZER, M., FEILEN, M., LEHNERT, J., URBANSKY, R., SAUER-GREFF, W. Technical feasibility study and field trial concept for DRM-based digital radio in the VHF-FM radio band. In Proceedings of the 7th Workshop Digital Broadcasting. Fraunhofer Institute for Integrated Circuits IIS Erlangen, Germany, Heinz Gerhauser (Ed.), 2006, p. 67–72.
In this paper, a cascade structure of nonlinear digital predistorter (DPD) synthesized by the direct learning adaptive algorithm is represented. DPD is used for linearization of power amplifier (PA) characteristic, namely for compensation of PA nonlinear distortion. Blocks of the cascade DPD are described by different models: the functional link artificial neural network (FLANN), the polynomial perceptron network (PPN) and the radially pruned Volterra model (RPVM). At synthesis of the cascade DPD there is possibility to overcome the ill conditionality problem due to reducing the dimension of DPD nonlinear operator approximation. Results of compensating nonlinear distortion in Wiener–Hammerstein model of PA at the GSM–signal with four carriers are shown. The highest accuracy of PA linearization is produced by the cascade DPD containing PPN and RPVM.
LEGARDA, J. Feedforward Amplifiers for Wideband Communication Systems. Dordrecht: Springer, 2006.
In this paper, the energy efficiency (EE) of downlink distributed antenna system (DAS) with multiple receive antennas is investigated over composite fading channel that takes the path loss, shadow fading and Nakagami-m fading into account. Our aim is to maximize EE which is defined as the ratio of the transmission rate to the total consumed power under the constraints of maximum transmit power of each remote antenna. According to the definition of EE and using the upper bound of average EE, the optimized objective function is provided. Based on this, utilizing Karush-Kuhn-Tucker (KKT) conditions and mathematical derivation, a suboptimal energy efficient power allocation (PA) scheme is developed, and closed-form PA coefficients are obtained. The developed scheme has the EE performance close to the existing optimal scheme. Moreover, it has relatively lower complexity than the existing scheme because only the statistic channel information and less iteration are required. Besides, it includes the scheme in composite Rayleigh channel as a special case. Simulation results show the effectiveness of the developed scheme.
RAPPAPORT, T. S. Wireless Communications: Principles and Practice. 2nd ed. Prentice Hall PTR, 2001. ISBN: 0130422320.
LOMBARDO, P., FEDELE, G., RAO, M. M. MRC performance for binary signals in Nakagami fading with general branch correlation. IEEE Transactions on Communications, 1999, vol. 47, no. 1, p. 44–52. DOI: 10.1109/26.747812.
This paper presents an efficient parallel processing architecture using multi-core Digital Signal Processor (DSP) to improve the capability of real-time imaging for Frequency Modulated Continuous Wave Synthetic Aperture Radar (FMCW SAR). With the application of the proposed processing architecture, the imaging algorithm is modularized, and each module is efficiently realized by the proposed processing architecture. In each module, the data processing of different cores is executed in parallel, also the data transmission and data processing of each core are synchronously carried out, so that the processing time for SAR imaging is reduced significantly. Specifically, the time of corner turning operation, which is very time-consuming, is ignored under computationally intensive case. The proposed parallel architecture is applied to a compact Ku-band FMCW SAR prototype to achieve real-time imageries with 34 cm x 51 cm (range x azimuth) resolution.
PALM, S., WAHLEN, A., STANKO, S., et al. Real-time onboard processing and ground based monitoring of FMCW-SAR videos. In Proceedings of the 10th European Conference on Synthetic Aperture Radar (EuSAR). Berlin (Germany), 2014, p. 1–4. ISBN: 9783800736072.
JOHANNES, W., STANKO, S., WAHLEN, A., et al. Implementation of a 35 GHz SAR sensor and a high resolution camera to enable real-time observation. In Proceedings of the 10th European Conference on Synthetic Aperture Radar (EuSAR). Berlin (Germany), 2014, p. 315–318. ISBN: 9783800736072.
The work presented in this paper describes a novel approach for automatic video tracking of visual degraded air vehicles in daylight with sky background. The offered and applied video object tracking method is based on Histogram Probabilistic Multi Hypothesis Tracker algorithm. The H-PMHT is an expectation maximization based algorithm developed for tracking objects in intense clutter environment by using intensity modulated data streams. Basically H-PMHT algorithm is suitable for linear-Gaussian point spread function case. However, recent studies have indicated that the algorithm is also applicable for non-linear and non-Gaussian target shapes. Thus H-PMHT becomes a suitable alternative for tracking applications with sonar, high resolution radars,IR, UV sensors and cameras. In this work H-PMHT algorithm is used for video tracking of visual degraded air vehicles. For this purpose RGB video data is processed by using a reciprocal pixel intensity measurement for meeting the requirements of the tracking process. A simulation study is conducted in order to demonstrate the video tracking performance of H-PMHT against visual degraded air vehicles. Also the results obtained with H-PMHT algorithm are compared with the results of amplitude information added Interacting Multi Model Probabilistic Data Association algorithm.
DAVEY, S J., WIENEKE, M. Tracking groups of people in video with histogram-PMHT. In Defense Applications of Signal Processing (DASP) Workshop. Coolum (Australia), 2011, p. 1–11.

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