In his latest white paper, Martin Griffiths, Managing Director of Forensic RF provides an exhaustive explanation of what the Modem State LIMSRV is and describes how it should be interpreted.
The paper offers reassurance to RF technicians that have seen this state within their evidential RF readings and have been uncertain what it means and whether it can be relied upon as part of an evidential RF Survey.
This white paper is designed to offer a technically complete definition of a Modem state recorded by Quectel Modems (which are installed in Lima CM) called LIMSRV. This Modem state may periodically be recorded in RF Survey results. There are currently questions and some confusion in relation to how LIMSRV rows of data should be interpreted and whether LIMSRV measurements are representative of viable serving cells or not and most importantly whether LIMSRV measurement rows can be considered evidentially sound.
It is important to acknowledge that any cellular Modem which adheres to 3GPP Specifications will have exactly the same the LIMSRV state condition which could be seen in the same way that Lima CM displays it if a device makes this data available (which generally they don’t). This LIMSRV state is therefore not limited to Quectel Modems, it exists in every standards compliant cellular Modem on the planet and will record this state within their log files if and when they occur.
The overall objective of this paper is to ensure that the RF Community have absolute confidence in the evidential veracity of radio surveys undertaken and the data recorded by Lima CM.
You can download and read the full white paper HERE