為了智慧電網的發展，目前已有許多窄帶電力線通訊（PLC）產品正在積極研發中，預計在不久後上市，以因應全球的環保產業。眾所皆知，電力通訊的複雜的敏感性及變化無常的衰減都是來自於電器負載及電磁干擾，為了在電力線上可靠且穩定的傳輸數位訊息，我們有迫切的必要去建立乾淨環境的電力線通訊模擬環境，例如在沒有電器的環境下量測。然而，透過反覆量測，可以發現通道長度、材質及類型都是影響通訊品質的原因之一。
首先，我們設置不同情境下的量測架構，有鑑於此，不同長度導線的衰減量測亦可實現。事實上，在某些環境下，我們發現窄帶電力線通訊頻帶之中有共振現象存在，這使得訊號呈現非線性放大導致嚴重失真，我們提出一通道模型用以預測不同電力線通道的共振頻帶，而模擬結果顯示與量測結果是同步的。透過本文所提出的通道模型，可以提供更準確的通道響應資訊用以改善訊號品質。此外，本文亦將量測之雜訊以數學加以建模，而模擬的結果亦與量測結果相對照。

Currently a number of narrowband power line communications (PLC) products aimed for smart grid have been under development and soon will be marketed to meet the demand for green industry worldwide. To fulfil reliable transmission of digital information over power line, commonly known for its susceptibility to complicated and fickle impairments due to time-varying electric loads as well as electromagnetic disturbances, it is imperative to investigate the narrow-band power line transmission model under a relative clean environment, i.e. in the absence of electrical appliances, through intensive measurements. Indeed, it has been well known that a number of primary factors affecting signalling quality over power line consist of its material, length, and even the wiring connection type.
We first demonstrate the measurement framework under a variety of scenarios. In view of this, the attenuation of signalling over twisted pair power lines of different lengths can be realized. Indeed, we observe that there exists resonant frequency within frequency range of interest for narrowband PLC systems in certain circumstance, leading to severe signal distortion from the saturated zone of low-noise nonlinear amplifier. A channel modelling is further proposed to predict the resonant frequency, which varies with power line length. The simulation results indicate the proposed channel modelling can fairly match their measured counterparts, improving signalling quality thanks to better knowledge on channel frequency response. In addition, noise measurement coupled with mathematical modelling is conducted. Simulations also coincide with measurements.

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