2. Background

The Ministry released in May 2007 an engineering discussion paper with the purpose of consulting industry on the potential introduction of digital trunk radio technologies in the 800 MHz TS band. This consultation process was put in place to address an expressed interest from band users in deploying new and more efficient technologies. The outcomes of this consultation were published in December 2007, identifying the following key aspects:

• TETRA and APCO P25 were identified as the preferred digital technologies;
• digital technologies to share the band with analogue systems;
• maintaining existing band plans and including a provision to allow 12.5 kHz channels;
• updating operational policy to permit digital land mobile emissions in the 800 MHz TS band;
• ensuring coexistence between digital standards and incumbent analogue systems.

This last point on technology coexistence became an outstanding engineering issue requiring further analysis. In order to address this point, a technical report was prepared and circulated for consideration by parties that had indicated an interest in the 800 MHz TS band. This technical report built upon, and fine tuned the results obtained in the initial consultation paper. This was required in order to ensure interference mitigation between multiple digital technologies and minimal impact on existing analogue services.