{'fraction_non_alphanumeric': 0.03185955786736021, 'fraction_numerical': 0.005851755526657998, 'mean_word_length': 5.035294117647059, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Empirical measurements of the low-frequency power-line communications channel in rural North America

This paper addresses power-line communication (PLC) for automated metering infrastructure (AMI) and automated meter reading (AMR) applications in North America, with specific focus on the physical layer. FCC regulations permit powerline communication systems in the US to use the band from 9 kHz to roughly 500 kHz. This paper presents channel and noise characteristics in this band, based on field tests. It is shown that the main challenge in communicating in this band is severe signal attenuation by service transformers. In rural areas, these transformers supply eight or fewer end points on average. Consequently, it is not economical to use a bridge device across each transformer. Rather, one router is placed on the medium voltage line for every few service transformers. We consider the channel between a concentrator or a router on the medium voltage line (around 7.2 kV), and low-voltage (around 110V) end points connected to transformers some distance away on the medium voltage line. The signal-to-noise ratios observed in such a link, and implications for signal design, are studied. Data is provided on all modem connection scenarios, including medium voltage to low voltage (MV→LV), low voltage to medium voltage (LV→MV), and medium voltage to medium voltage (MV→MV). These results are intended to define requirements for a PHY / MAC communication system that can support the AMI application in such channel conditions.