Stability Analysis and Hardware Resource Optimization in Channel Emulator Design

Abstract

In this work, we optimize hardware consumption in Rayleigh channel generation. Due to the advantage in saving memory resource, a recursive-structure-based channel generator is considered in this paper. We first investigate the long-term accuracy of channel generation by the recursive structure. Afterwards, we calculate the optimum bit width and channel update period at which normalized mean-square-error (MSE) minimization is achieved. The minimization is under a constraint of a upper bound on a bit rate which is defined as the ratio of bit width over channel data update period. Via experiments on a Xilinx FPGA chip, the optimization in the generation of Rayleigh channel with U -shaped spectrum saves more than 31% bit rate for the normalized MSE of 1.8 × 10 −6 . According to our experiments, the 31% bit rate reduction can save up to 174 slices, 31 flip-flops, and 390 LUTs.Index Terms-Fading channel generator, field-programmable gate array (FPGA), joint optimization over sampling period and bits, stability of an iterative structure based sinusoid generator, sum of sinusoids.

A Flexible FPGA-Based Channel Emulator for Non-Stationary MIMO Fading Channels

“…Several methods for generating the channel fading coefficients, i.e., SoC method, Doppler filter method, AR method, and their derivatives can be addressed in [10,11,28,29]. However, these methods can only be used for stationary channels with fixed channel parameters.…”

“…However, these emulators are very large, expensive, and complicated, and mainly developed for the standard channel models, which are all based on the wide-sense stationary (WSS) assumption. Meanwhile, various academic researches on hardware emulation can be found in [9][10][11][12][13][14][15][16][17][18], which were focused on the emulation of stationary channel models [9][10][11][12]. However, recent measurements have proved that the stationary channel model is not suitable for certain propagation scenarios [13][14][15][16][17][18], such as high-speed train (HST) [16,17], vehicle-to-vehicle (V2V) [13][14][15], and unmanned aerial vehicle (UAV) channels [18].…”

Study on a Low-Complexity ECG Compression Scheme With Two-Tier Sensors

“…In a partial summarization of the quantization on the primary sensor, the histogram of the first order differential ECG signal is calculated first; second, via curve fitting, a PDF in an explicit form is calculate to approximate the histogram; third, the number of the bits for the quantization is determined; fourth, the codebook and quantization zones are determined according to (22) and (23) respectively.…”

Hardware Implementation of Overlap-Save-Based Fading Channel Emulator

“…Main prior solutions for real-time hardware implementations of different channel emulators can be found in [11][12][13][14][15]. Solutions in [11][12][13][14] are SOS-based whereas the solution in [15] represents a novel Sum-of-Frequency-Modulation (SoFM) method used in a Multiple-Input Multiple-Output (MIMO) system. While looking at the OLS-based emulator presented in [10], implementation complexity is provided only in terms of complex arithmetic operations.…”