Transmitted Reference Ultra Wideband Receiver Research Articles

A Differential Transmitted Reference UWB Receiver Using Time Reversal Technique

A Differential Transmitted Reference (DTR) system is analyzed for Ultra Wideband (UWB) communications in a multipath propagation environment with single user transmitted. In order to improve the data rate, The Time-Reversal technology is proposed for the DTR receiver in the paper, which can also resist the influence of Inter/intra Symbol Interference (ISI). Computer simulation is conducted in the presence of an IEEE802.15.3a CM2 channel with Scholtz’s pulse. Analysis and simulation are both shown that the TiR-DTR receiver can improve the data rate of UWB system.

CLOSED-FORM PDF FOR MULTIUSER TR-UWB SYSTEMS UNDER GAUSSIAN NOISE AND IMPULSIVE INTERFERENCE

In most existing transmitted-reference ultra-wideband (TR-UWB) communication systems, receivers use the standard Gaussian approximation (SGA) for multiuser interference (MUI). It is an assumption used in most conventional multiuser systems, where the MUI tends to a Gaussian process by the central limit theorem, and convergence is relatively fast with respect to the number of users. However, for TR-UWB systems which are developed for short-range applications, we have a small number of active users. In this case, significant performance degradation is found in TR-UWB receivers due to the impreciseness of SGA. In this paper, we show that the Middleton class-A model is a more appropriate statistical model for MUI modeling in TR-UWB systems than the often used SGA. A closed-form expression for the probability density function (PDF) of the TR-UWB system under MUI, Gaussian noise and impulsive alpha-stable interference is developed. All these analytical results are confirmed by numerical simulations. (17 References).

A window detection technique with adjustable threshold for transmitted reference receivers

Abstract This paper presents a threshold decision circuit with an adjustable detection window designed in a 90-nm IBM CMOS technology. Together with an RF mixer, the decision Section realizes the circuit implementation of the back-end of a transmitted reference ultra wideband receiver, which is yet to be reported in literature. The proposed circuit is built on a differential amplifier core and avoids the use of integrator and sampling blocks, which reduces the device burden necessary for the architecture. Moreover, the detection window threshold of the design can be regulated by three independent factors defined by the circuit elements. The circuit is tested at an input data rate of 0.1∼2.0 Gbps and the core decision section consumes 9.14 mW from a 1.2-V bias supply (with a maximum capacity/Pdc ratio of 218.8 GHz/W). When compared against other reported decision blocks, the proposed detection circuit shows improved performance in terms of capacity and power requirement.

Average SINR Analysis of DS-BPSK UWB Systems With IPI, ICI, ISI, and MAI and Its Application

Analytical expressions for the average output signal-to-interference-plus-noise ratio (SINR) of direct-sequence (DS) binary-phase-shift-keying (BPSK) ultra-wideband (UWB) receivers are derived using the IEEE UWB channel models. The derivation takes into account the interpath interference, the interchip interference (IPI), the intersymbol interference (ISI), and the multiple-access interference (MAI). The effects of the spreading gain and the pulse duration on the average output SINR are examined. Using these results, the optimal integration interval for a transmitted reference UWB receiver is studied.

Baseband implementation of OTR-UWB receiver using FPGA

This paper presents a new transmitted reference ultra-wideband receiver, which utilizes the orthogonal property of even and odd order derivatives of Gaussian pulses in neighboring chips for synchronization. This system, referred to as orthogonal TR-UWB (OTR-UWB), employs only a single spreading code, which results in much lower mean detection time compared to DS-UWB systems since smaller search space is involved for coarse acquisition. The hardware complexity for OTR-UWB receiver is significantly reduced against conventional TR-UWB systems. In addition, simulation results show that bit error rate (BER) performance is improved, while the new system is capable of supporting higher data rates. Also, this paper presents a technique for implementing low rate OTR-UWB system in FPGA by combining pipeline scheduling, parallel component, and module selection. The system has been implemented on two FPGA platforms from ALTERA and XILINX, CycloneII (EP2C35F672C6) and Spartan 3 (3s4000fg676-5)with a bit-rate of 25Mb/s without using equalizer. It incorporates 4-bit of resolution with 8GHz frequency sampling rate for analog to digital conversion realized by parallel low frequencyADC blocks. Gate estimation and power analysis are performed by Quartus II 7.1 (ALTERA) and ISE 8.1 (XILINX) softwares.

A Novel Class of Algorithms for Timing Acquisition of Differential Transmitted Reference UWB Receivers: Architecture, Performance Analysis and System Design

This paper deals with the analysis of the timing acquisition (synchronization) process in Impulse Radio (IR-) Ultra Wide Band (UWB) systems based on Differential Transmitted Reference (DTR) receiver architectures. The fundamental contribution includes a theoretical framework for timing acquisition analysis, which is not only able to describe the first moment (Mean Acquisition Time, MAT), and the second moment (standard deviation of the acquisition time) of the acquisition process, but which also provides a consistent and comprehensive analysis of the probability mass function of the acquisition time, i.e., Acquisition Time Mass Probability. In particular, the specific novelty insights of this paper are as follows: (i) the proposal of a new synchronization algorithm, which is based on a two-step approach and relies on the specific characteristics and peculiarities of DTR receivers, as well as the analysis of its performance via a framework based on the theory of Markov processes; (ii) the exploitation of the LATTICE- POISSON algorithm to accurately estimate the Acquisition Time Mass Probability and Overall Acquisition Probability P <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">D</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">(ov)</sup> , i.e., the probability to get synchronized before a given time; (iii) the performance analysis and comparison of one-step and two-step solutions with respect to the acquisition threshold; and (iv) the analysis of two approaches to estimate MAT and P <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">D</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">(ov)</sup> in multipath fading channels, i.e., "Tacq Average" and "Pd Average', which are shown to lead to different results in different scenarios. We observe that restricting the analysis to the MAT may lead to hasty conclusions about the effect of the acquisition threshold on the design of DTR receivers, thus substantiating the need for a more general analysis using P <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">D</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">(ov)</sup> , as well as the necessity of specifying the characteristics of the wireless channel (e.g., quasi-static, slowly- or fast-fading) for an accurate performance analysis.