This Standard provides physical layer performance standards under standard conditions for 12.5 kHz channelization digitally modulated radio equipment used in the Private (Dispatch) Land Mobile Services that employs a Two-Slot Time Division Multiple Access method for transmission and reception of voice or data using digital techniques, with or without encryption, with a frequency of 1 GHz or less. The definition and description of the system in which this equipment operates is given in the Project 25 Two-Slot TDMA Overview document (TIA TSB-102.BBAA). The physical layer description is given in Project 25 Phase 2 Two-Slot Time Division Multiple Access Physical Layer Description (TIA- 102.BBAB). The media access control is given in Project 25 Phase 2, Two-Slot Time Division Multiple Access Media Access Control Layer Specification- Trunked Voice Services, (TIA-102.BBAC).

Two performance levels have been distinguished herein for certain equipment characteristics. The performance level of Class B is comparable to the performance level for 12.5 kHz analog radio equipment in TIA/EIA-603-D, Land Mobile FM or PM Communications Equipment. Class A describes a higher level of performance for more stringent applications. Should Federal Communications Commission (FCC) requirements as listed in 47 CFR, Code of Federal Regulations, Telecommunication, become more stringent than any standard contained herein, the FCC requirements supersede these.

The standards in this document may be applicable to applications other than those specifically addressed in Project 25. Use of these standards is encouraged for any application of similar equipment; however, the user should review the required standards needed for the specific application.