Rover HD TAB 700 - Abbreviations & Technical Terms

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ABBREVIATIONS & TECHNICAL TERMS
•฀APID (Audio Packet Identifier): Audio reception parameters in the MPEG data stream.
•฀aBER (Bit Error Rate after Viterbi): Ratio of the transmitted bits to the erroneous bits after
Reed Solomon (Viterbi).
•฀BCH (Bose Chaudhuri Hocquenghem): External error protection decoder.
•฀BER (Bit Error Rate): The bit error rate shows the quality of the DVB signals. It displays the
number of erroneous bits in relation to all the transmitted bits.
•฀bBER (Bit Error Rate before Viterbi): Ratio of the received bits relative to bits that have errors
before Reed Solomon (Viterbi).
•฀CBR (Constant Bit Rate): Is used for MPTS measurements, cf. VBR.
•฀C/N (Carrier to Noise): Difference between the carrier signal and noise level in dB; see also
S/N.
•฀EVM (Error Vector Magnitude): Measures deviation of the transmitted symbols to the ideal
constellation, measured in dB.
•฀FEC (Forward Error Correction): Forward Error Correction, e.g. in case of the code rate ¾, ¾
of the information is user data, ¼ of the data come from the Viterbi correction.
•฀Guard Interval: Guard interval by extending the symbol through a gap. Due to this, good
reception is possible even in case of strong reflections.
•฀LCN (Logical Channel Numbering): Logical channel sorting performed by the provider.
•฀LDPC (Low Density Parity Check): A new error protection method applied in DBV-S2
(Gallager codes). Inner error protection; code rates from 1/2 to 9/10.
•฀MER (Modulation Error Rate): MER is the ratio of the average signal power to the average
error power in dB. It is a kind of a C/N measurement which gives information whether the
receiver is able to demodulate the received signal.
•฀MPTS (Multiple Program Transport Stream).
•฀NID (Network Identification): Network ID or channel identification number between 0 and
8191.
•฀NIT (Network Information Table): Contains, for example, information about all available
transponders, PIDs, downlink frequency, polarisation, next transponder for the scan;
transmitted in the multiplexer transport stream.
•฀NsMargin (Noise Margin): Signal to Noise Ratio margin.
•฀OMI (Optical modulation index).
•฀PER (Packet Error Ratio): The Packet Error Ratio displays the number of incorrectly received
data packets relative to the total number of transmitted packets (after Viterbi).
•฀QEF (Quasi Error Free): Bit error rate equals 2.00e-4.
•฀Noise Level: Sum of noise factor and thermal noise floors. Noise is created by physically
caused molecular motion in electrical conductors.
•฀RMS (Root Mean Square): Method of a square mean value determination.
•฀S/N (Signal to Noise): Difference between the wanted signal and the noise level in dB;
S/N ≈ C/N + 1,5; see also C/N.
•฀SPTS (Single Program Transport Stream).
•฀TSID (Transport Stream ID): Transponder/multiplex ID.
•฀VBR (Variable Bit Rate): Is used for MPTS measurements, cf. CBR.
•฀VPID (Video Packet Identifier): Video reception parameters in the MPEG data stream.