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Many circuits can be modeled using cascaded transmission line segments. The method is so general that microwave and acoustic circuits can be modeled. This paper uses transmission lines to model a brass musical instrument mouthpiece and develop a lumped element model that can be used to simulate a cornetto
Design and measurements of a room temperature 700 MHz - 1400 MHz low noise amplifier (LNA) in 90-nm bulk CMOS, intended for use in the Canadian large adaptive reflector (CLAR) radio telescope, are presented. The new bandwidth constrained LNA noise figure optimization and broad-banding technique as well as the importance of substrate shielding are discussed. The amplifier has 0.35 dB noise figure while...
In this paper, we propose a new jointly optimized linear prefilter and nonlinear vector perturbation approach to the multiple transmit multiple receive (MIMO)-multiuser (MU) precoder system. As a closest lattice point search problem in the vector perturbation based method, the suboptimal QRD-M is used. For the prefilter design, the weighted MMSE criterion is used. Simulation results show that the...
In this paper, we consider the decision fusion of Rayleigh fluctuating targets in multi-radar sensor networks. Decision fusion and data fusion in wireless sensor networks (WSNs) has been widely studied in order to save energy. Radar system as a special sensor network, when implemented for battlefield surveillance, faces bandwidth constraint in real-time applications instead of energy restriction....
In this paper, we present a survey of noncooperative game theory as an analysis tool in multiple antenna systems and summarize the major conclusions drawn. We study various multiple antenna systems and show how the lack of cooperation among the different entities is used by game theory to find fundamental limits and design algorithms that achieve these limits
Complex orthogonal designs of maximum possible rate of full, 3/4, and 3/4 have been presented for 2, 3, and 4 transmit antennas respectively. For 5 and 6 transmit antennas, two generalized complex orthogonal space-time block codes of rates 7/11 and 3/5 were proposed recently. In this paper, we propose three complex orthogonal space-time block codes whose rates are up to 2/3, 2/3, and 5/8 for 5, 6,...
A fully-integrated UHF CMOS transceiver with resonant transmit/receive (T/R) switch is reported. The transceiver's power amplifier (PA) and LNA are simultaneously connected to the antenna and isolated from each other by going to high impedances during receive and transmit respectively. A two-stage single-ended PA produces 19 dBm output power and 36% PAE is measured at 400 MHz. The LNA has 22 dB gain...
Coherent signaling over a fading channel requires the receiver to have knowledge of the current fading state (CSIR). In order to proactively prevent outages, the transmitter requires knowledge of the fading state (CSIT) to perform power control. Typically, the channel state is estimated by using a training signal, and the channel state information contains some error. In this work, we examine the...
This paper presents two initialization schemes: phased array-assisted initialization and switched-beam element phased array-assisted initialization, for a constant modulus algorithm (CMA). Both techniques utilize a beam with maximum received power obtained by beam-switching of array antenna to initial CMA. The techniques can significantly improve convergence properties of CMA, which is employed for...
We propose a high-accuracy, low-cost UWB-IR wireless location system based on the quasi TDOA method. The system consists of anchor nodes, a synch node and a location server. The anchor nodes synchronize each other as regulated by the synch node so that synchronization is always precise in the location process. To make the anchor node simple, the location system uses acquisition and tracking functions...
In this paper, we propose an algorithm, namely, beam synthesis (BES) method for updating the beamforming weights from one TV channel to another TV band in cognitive radio based wireless regional area network (WRAN) communications systems. The proposed BES method tries to constrain not only the same null positions, but also the same main beam positions for different TV channels. The proposed method...
In WCDMA receivers, WCDMA modulated adjacent channel interferers (ACI) can distort the useful signal due to non linearity of the front end RF components. Non linearity of the RF front end transfers the modulation of the transmitter (TX) leakage onto the ACI, resulting in cross-modulation distortion. In addition to this, if the ACI signal is strong, it would undergo spectral re-growth and some fraction...
In this paper we present a novel approach for high precision clock synchronization in wireless systems. A concept similar to the standard FMCW (frequency-modulated continuous wave) radar principle is used to estimate the offset in time and in frequency between two wireless communication units. The novel approach allows for a synchronization of both offsets significantly below 100 ps and 10 Hz, respectively...
The increasing need for functional flexibility in radio systems to accommodate the proliferation of wireless standards will make implementation of wireless standards on reconfigurable radio platforms the only viable option in the coming years. We address the choice of the reconfigurable analog receiver architecture for mobile, battery-powered terminals and analyze in detail two extreme cases: a state-of-the-art...
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