Repurposing Cellular Reference Signals: Accurate RSRP Measurements with Mobile Phones

Reference signals in both LTE and 5G cellular networks present an untapped and abundant signal of oppor-tunity for high quality radio frequency (RF) propagation measurements. Commercial-off-the-shelf mobile phones continuously capture and report Reference Signal Received Power (RSRP) measurements, making them an easily crowdsource-able data source for RF propagation modeling in path geometries and frequencies relevant to cellular network communications. However, it remains unclear whether crowdsourced mobile phone RSRP measurements can meet the stringent accuracy requirements of measured propagation data in support of empirical model validation and improvement. This investigation details an extensive measurement campaign and analysis to quantify the variability between, and accuracy of, RSRP measurements from nine unique mobile phone models. We find that 10% of the measured RSRP variance is due to the inherent differences between phone models. We also find, that the mean RSRP accuracy of the combined phones is within ± 1.5 in the most used frequency bands, suggesting that measurements from a diversity of mobile phone models, inherent to crowdsourced measurements, can be leveraged to estimate a highly accurate mean power.