Cellular Interference, Security Part of Latest P25 Standards Work
Thursday, March 26, 2020 | Comments

The Project 25 Technology Interest Group (PTIG) highlighted accomplishments and work in progress for 2020 from the Telecommunications Industry Association (TIA) TR-8 committee. New work includes addressing interference with 700/800 MHz cellular systems and security features, among others.

A revision to the TSB-88.1-E Wireless Communications Systems Performance in Noise and Interference-Limited Situations Part 1: Recommended Methods for Technology- Independent Narrowband Performance Modeling Telecommunications Systems Bulletin is under consideration. This work will look into possible near-far interference issues for radios with wide preselectors in proximity of short-tower cellular systems at 700/800 MHz.

In the area of security, a definition of a link layer encryption security service is in progress. This is the first big new technology upgrade for improved security for all air interfaces of P25. It protects control channel control messages and hides group and individual IDs. An addendum to the Key Fill Interface Standard is also in progress. This will enable key fill device (KVL) interface to a KMF, an authentication facility and another key fill device.

In the broadband area, the definition of Third Generation Partnership Project (3GPP) mission-critical standard services interworking with TIA LMR standard services is in progress. This document will describe interworking of features such as group and individual calls that are common between 3GPP Long Term Evolution (LTE) standards and P25 trunking, P25 conventional and analog conventional FM LMR standards. This document will be a basis for the modification of the Inter RF Subsystem Interface (ISSI), Console Subsystem Interface (CSSI) and Digital Fixed Station Interface (DFSI) standards to enable interface with a mission-critical LTE interworking function (IWF).

Several air interface documents were completed in 2020. A revision to the TIA-102 Documentation Suite Overview Telecommunications Systems Bulletin was approved for publication. This revision updates the documentation suite and feature information to align with new publications that have occurred during the past three years.

A revision of American National Standards Institute (ANSI)/TIA-4950-B “Requirements for Battery-Powered, Portable Land Mobile Radio Applications in Class I, II, and III, Division 1, Hazardous (Classified) Locations” standard was approved for publication. This revision contains UL-recommended improvements/clarifications to the document regarding electrical protection parameters updates. In addition, an addendum to the Over the Air Rekeying Messages and Procedures standard was approved for publication. This will allow single-key radios to use any encryption key identification (ID) and will allow multikey radios to use any encryption key ID to ensure interoperability between single key and multikey equipment.

Several air interface updates are in progress. Creation of a High Signal Strength Intermodulation Rejection Test is in progress. Measurement Method for FDMA receivers completed ballot, and technical comments are being addressed. The companion FDMA Performance Recommendations standard has been through one review cycle. This test will measure the ability of a P25 or analog conventional FM receiver to reject an unwanted broadband base station signal, thereby preventing degradation to the reception of a desired signal. Performance specifications are expected to follow completion of the measurement method.

An addendum to the Trunking Interoperability Test standard is in progress. This addendum will clarify the testing procedures for systemwide call. In addition, group regrouping for the trunking ISSI/CSSI standard is in progress. This work will enable dispatch equipment connected to trunking infrastructures via the ISSI/CSSI to control group regrouping services. Note the control channel messaging for these services has already been standardized.

A revision to the Trunking ISSI/CSSI Messages and Procedures standard is in progress. This document will merge two previously published addendums into the previously published parent document. An addendum to the Trunking ISSI/CSSI Messages and Procedures standard is in progress. This addendum will describe how the ISSI/CSSI interface may be used to connect a trunking RF subsystem to IWF to enable interoperable services between P25 Systems and LTE mission-critical systems.

The full PTIG document is here.

Would you like to comment on this story? Find our comments system below.

Post a comment
Name: *
Email: *
Title: *
Comment: *


No Comments Submitted Yet

Be the first by using the form above to submit a comment!


August 2022

7 - 10
APCO Conference and Expo 2022
Anaheim, California

More Events >

Site Navigation