Advanced emulation of channel transfer functions for performance evaluation of powerline modems

Abstract

Typical powerline networks feature frequencyselective attenuation which has a relatively high dynamic range and sometimes large notches. This fact is usually idealized with flat in-band attenuation during the performance evaluation of PLC modems. Thus the noise margin under these channel conditions cannot be measured. Inserting L-C-R resonance circuits between devices under test (DUT) can introduce some kind of frequency-dependent attenuation of the transmit signal, However this method suffers from low flexibility, low accuracy and high complexity. This paper proposes a channel emulatorbased platform for the performance test of powerline communications (PLC) modems in frequency range up to 500 kHz. It is capable of emulating the frequency-dependent channel characteristics accurately and conveniently. The result of margin tests shows that different techniques as well as different implementations of the same technique have different performance with the same channel; single-carrier modulations have higher margins as multi-carrier and spread spectrum modulations. All these facts can only be revealed by employing realistic channel conditions, therefore the flat attenuation is insufficient for a comprehensive and persuasive performance evaluation.

Power line communications (PLC) technology: More than 20 years of intense research

“…However, the indoor channel capacity may reach 600 Mb/s. More can be found in the works of Gotz et al, Bausch et al, and Liu et al for channel characterisation and in the works of Bauer et al and Liu et al for channel emulation.…”

Automotive Power-Line Communication Channels: Mathematical Characterization and Hardware Emulator

“…In the literature, several methods for AWGN generation are known [26], such as for example the Box-Muller algorithm, the central limit theorem (CLT) method, the Ziggurat method and the polar method. An extensive work on Gaussian noise generators is available in [27] and some of the reported methods have also been experimented in the context of the power line channel emulation [28]. In most cases, the Box-Muller approach is preferred and actually selected in several practical implementations, including a proprietary IP unit available from Xilinx.…”

Research on Broadband Channel Characteristics and Hardware Testbed for Power Line Communication System

“…It focused on the recently proposed PLC solution for narrow-band communication by the Spanish electric utility Iberdrola: PRIME [3]. This contribution aims at discussing a channel estimation methodology that is constituted by a sounding technique for channel estimation, a time synchronization technique, and a measurement setup [4][5][6]. This work presents a PLC channel model for the broad-band characterization of power lines in presence of time variation of the loads, the model is characterized by taking into account both measured and geometrical channel characteristics and can easily be used to take into account also the presence of noise [7,8].…”