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A 1K-Gate GaAs Gate Array
Full text link1984 IEEE International Solid-State Circuits Conference (ISSCC 84), Wednesday, FEB 22, 1984 at Continental Ballrooms 6-9, 9:00 a.m
Modeling of High-Speed, Large-Signal Transistor Switching Transients from s-Parameter Measurements
Full text linkA new technique has been developed to derive the large-signal transient response of semiconductor devices from small-signal frequency response data. The large-signal switching response can be calculated for an arbitrary input signal voltage and rise time. This new technique utilizes the Fourier transformation to combine arrays of small-signal data to compute the response waveform. The input waveform is decomposed into a superposition of small pulses. The response to each pulse is obtained by Fourier transformation techniques, using s-parameter data at appropriate bias points. The sum of these responses approximates the overall transient response. Simulations were performed for a GaAs MESFET for step inputs with the rise times of 8 ns and 150 ps. Good agreement was obtained between simulated waveforms and measured output waveforms in rise time, magnitude, and waveform shape. This algorithm is general and will work for other measured small-signal transfer parameters as functions of frequency and bias
Modeling of high-speed, large-signal transistor switching transients from s-parameter measurements
Full text linkA new technique has been developed to derive the large-signal transient response of semiconductor devices from small-signal frequency response data. The large-signal switching response can be calculated for an arbitrary input signal voltage and risetime. This new technique utilizes the Fourier transformation to combine arrays of small-signal data to compute the response waveform. The input waveform is decomposed into a superposition of small pulses. The response to each pulse is obtained by Fourier transformation techniques, using s-parameter data at appropriate bias points. The sum of these responses approximates the overall transient response. Simulations were performed for a GaAs MESFET for step inputs with the risetimes of 8 nsec and 150 psec. Good agreement was obtained between simulated waveforms and measured output waveforms in risetime, magnitude and waveform shape. This algorithm is general and will work for other measured small-signal transfer parameters as a function of frequency and bias.1981 International Electron Devices Meeting (IEDM 81
Report of Wireless Access & Multiple Antenna Technologies
Full text linkIn this deliverable, we address several aspects related to physical transmission and medium accessfor the links-on-the-fly concept. After a brief review of lossy forwarding and RESCUE requirements on the physical and medium access control layers, we present three parts: First, we study multiple-input multiple-output (MIMO) beamforming to improve system reliability and spectrum efficiency in the context of lossy forwarding, specifically a MIMO multi-relay system with random beamforming and limited feedback.The approach exploits link correlation information in order to mitigate error propagation effects. Twouser scheduling strategies are proposed and assessed by means of theoretical and numerical analysis. Second, we consider the relay network of toy scenario 1 as a virtual multiple-input single-output (MISO) system. Then, we evaluate the performance by employing lossy forwarding and investigate the tradeoff between high communication reliability (diversity gain) on the one side and high throughput for a fixed reliabilitylevel (multiplexing gain) on the other side. We compare the lossy forwarding scheme with the conventional decode-and-forward scheme in terms of diversity and multiplexing gain by means of theoretical and numerical analysis. Third, we extend the RESCUE system to a general multi-user multi-way relay network. Based on this model, we explore the use of coded random access as a promising wireless access technique and develop a framework that allows to investigate the combination of lossy forwarding and the coded random access schemes
Intermediate Results of Wireless Access and Multiple Antennas Technologies
Full text linkIn this deliverable intermediate results on multiple access and multiple antenna technologies forRESUE are described. We start with an introduction summarizing the requirements on the physical layerand multiple access technologies. The main part is dedicated to non-orthogonal multiple access, where we investigate the suitability of GFDM and IDMA for RESCUE requirements. We can show that both techniques are suitable for RESCUE. Initial considerations are carried out, how GFDM and IDMA can be combined to combine the benefits of both schemes. Furthermore, we describe a reduced-complexity algorithm for solving the power distribution for coordinated beamforming in a multi-relay scenario. It is shown that the describedalgorithm outperforms existing algorithms in terms of computational complexity and convergence speed