Wireless Communications Systems Performance in Noise and Interference- Limited Situations Part 1: Recommended Methods for Technology-Independent Narrowband Performance Modeling
|Publication Date:||1 November 2018|
The TSB-88.x Series The TSB-88.x series of bulletins gives guidance on the following areas:
• Establishment of standardized methodology for modeling and simulating narrowband/bandwidth
• Recommended datasets and propagation models that are available for improved results from modeling and simulation;
• Establishment of a standardized methodology for empirically confirming the performance of narrowband/bandwidth
• Combining the modeling, simulation and empirical performance verification methods into a unified family of data sets or procedures which can be employed by frequency coordinators, systems engineers, system operators or software developers;
The purpose of these documents is to define and advance a standardized methodology to analyze compatibility of different technologies from a technologyneutral viewpoint. They provide recommended technical parameters and procedures from which automated design and spectrum management tools can be developed to analyze proposed configurations that can temporarily exist during a "rebanding" or "narrowbanding" migration process as well as for longer term solutions involving different technologies.
As wireless communications systems evolve, it becomes increasingly complex to determine compatibility between different types of modulation, different channel bandwidths, different operational protocols, different operational geographic areas, and application usage.
Thus, spectrum managers, system designers and system maintainers have a common interest in utilizing the most accurate and repeatable modeling and simulation capabilities to determine likely system performance. With increasing spectrum allocation complexity, both in terms of modulation techniques offered, channel bandwidths available and in the number of entities involved in wireless communications systems, a standardized approach and methodology is needed for the modeling and simulation of these systems, in all frequency bands of interest.
In addition, after deployment, validation or acceptance testing is often an issue subject to much debate and uncertainty. Long after a system is in place and optimized, future interference dispute resolution demands application of an industry accepted and standardized methodology for assessing system performance and interference.
These documents contain recommendations for both public safety and nonpublic safety performance that are intended be used in the modeling and simulation of these systems. These documents also satisfy the need for a standardized empirical measurement methodology that is useful for routine proofof- performance and acceptance testing and in dispute resolution of interference cases that are likely to emerge in the future.
To provide this utility necessitates that manufacturers define various performance criteria for the different capabilities and their specific implementations. Furthermore, sufficient reference information is provided so that software applications can be developed and employed to determine if the desired system performance can be realized.
Wireless system performance can be modeled and simulated with the effects of single or multiple potential distortion sources taken into account as well as the defined performance parameters and verification testing. These include:
• Co-channel users
• Off-channel users
• Internal noise sources
• External noise sources
• Equipment non-linearity
• Transmission path geometry and transmission loss modeling
• Delay spread and differential signal phase
• Over-the-air and network protocols
• Performance verification
Predictions of system performance can then be evaluated based on the desired RF carrier versus the combined effects of single or multiple performance degrading sources. Performance is then based on a faded environment to more accurately simulate actual usage considering all the identified parameters and potential degradation sources.
It is anticipated that these documents will serve as a recommended best practices reference for developers and suppliers of land mobile communications system design, modeling, simulation and spectrum management software and automated tools.
This document, Part 1 of TSB-88-E, addresses performance modeling and the parametric values used to accomplish that modeling within the context described in §1.1, limited to frequencies below 1 GHz.