This standard specifies the parameters and methods for frequency planning for digital terrestrial television in conformity with GB 20600-2006.
This standard is applicable to the coverage network planning of digital terrestrial television broadcasting system in the VHF/UHF bands.
2 Normative References
The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, subsequent amendments to (excluding corrections to), or revisions of, any of these publications do not apply. However, all parties coming to an agreement according to this standard are encouraged to study whether the latest editions of these documents are applicable. For undated references, the latest edition of the normative documents referred to applies.GB 3174-1995 "Specifications of PAL-D Television System"GB/T 14433-1993 "Technical Specifications for Coverage Networks of Colour TV Broadcasting"GB 20600-2006 "Framing Structure, Channel Coding, and Modulation for Digital Television Terrestrial Broadcasting System (DTMB)"
3 Terms, Definitions and Abbreviations
3.1 Terms and DefinitionFor the purposes of this standard, the following term and definition applies.3.1.1
Wanted signal
The RF signal with information to be received.3.1.2
Unwanted signal
Other RF signal irrelevant to the information to be received.3.1.3
RF protection ratio
The minimum power ratio of wanted signal to unwanted signal at the normal receiving conditions, generally measured at the receiver inlet and represented by dB.
3.1.4
Time probability
The percentage of time when the signal field strength reaches or exceeds a certain given value to the observation time, at any measuring position if the signal varies with the time.
3.1.5
Location probability
The percentage of the location where a given value is reached or exceeded to the small measured area (typical value is 100m×100m) when the signal field strength varies with the locations to be measured.3.1.6
Minimum equivalent field strength
The minimum field strength to ensure the receiver on the digital terrestrial television can receive the signal normally without other signal interference.
Note: The power spectrum density of broadband signal is varied throughout the signal bandwidth, so the "equivalent field strength" is usually adopted instead of "field strength". The equivalent field strength is the irradiation field strength of the non-modulating signal, having the equal power with the broadband signal.
3.1.7
Minimum median equivalent field strength
The minimum median field strength to ensure the receiver on the digital terrestrial television can receive the signal normally considering that the statistical factors of wanted signal field strength will vary with the time and location.3.2 Abbreviations
For the purpose of this standard, the following abbreviations apply.
BER Bit Error Rate
C/N Carrier-noise ratio
MFN Multiple Frequency Network
PR Protection Ratio
QAM Quadrature Amplitude Modulation
SFN Single Frequency Network
TS Transport Stream
4 Terrestrial Television System
GB/T 26252-2010 The following standards are cited：
