Rohde & Schwarz CMU-K20, Руководство по эксплуатации

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Non Signalling: Connection Control CMU-K20/K21/K22/K23/K24
1115.6088.12 4.72 E-11
The training sequence is located in the middle of the symmetrical normal burst and is used for synchronization and
to assess the transmission conditions in the RF channel.
TB Useful Information Training sequence F F TB GP Useful Information
TB Tail bits (end or start bit) Bits 0 to 2, 145 to 147
Useful information Bits 3 to 59, 88 to 144
F Flag Bit, Stealing Flag Bits 60, 87
Training sequence Bits 61 to 86
GP Guard Period, transmission-free time of 8.25 bit periods
Fig. 4-33 Bit structure of a GSM normal burst
Compared to a normal burst, the access burst (see section
Limit lines (Power Configuration – Limit Lines)
on
page
4.32
) has a longer guard period (68.25 symbols instead of 8.25 symbols) whereas the useful duration is
shortened by 60 symbols.
Here the training sequence is used to distinguish different burst types: If a definite
training sequence is specified, the CMU only analyzes bursts with this training
sequence. The following settings are provided:
GSM 0 to 7 GSM standard training sequences
Dummy GSM-specific dummy burst
Off Measurement of all bursts regardless of their training sequence
GSM training
sequences
The 8 standard training sequences GSM 0 to GSM 7 are specified in the GSM
standard.
TSC training sequence code for numbering the sequences
Bit pattern 26-bit training sequence
They read as follows:
TSC Bit pattern (Bits No. 61 to 86)
0 0 0 1 0 0 1 0 1 1 1 0 0 0 0 1 0 0 0 1 0 0 1 0 1 1 1
1 0 0 1 0 1 1 0 1 1 1 0 1 1 1 1 0 0 0 1 0 1 1 0 1 1 1
2 0 1 0 0 0 0 1 1 1 0 1 1 1 0 1 0 0 1 0 0 0 0 1 1 1 0
3 0 1 0 0 0 1 1 1 1 0 1 1 0 1 0 0 0 1 0 0 0 1 1 1 1 0
4 0 0 0 1 1 0 1 0 1 1 1 0 0 1 0 0 0 0 0 1 1 0 1 0 1 1
5 0 1 0 0 1 1 1 0 1 0 1 1 0 0 0 0 0 1 0 0 1 1 1 0 1 0
6 1 0 1 0 0 1 1 1 1 1 0 1 1 0 0 0 1 0 1 0 0 1 1 1 1 1
7 1 1 1 0 1 1 1 1 0 0 0 1 0 0 1 0 1 1 1 0 1 1 1 1 0 0
Note: In Signalling Mode, no training sequence but signalling parameters
such as the color code of the base station can be specified for
analyzed signals. This also serves to search for bursts with a particular
characteristic.
Remote control
[SENSe:]RFANalyzer:TSEQuence <Number>
深圳德标仪器
135-1095-0799