Rohde & Schwarz EX-IQ-BOX, Руководство пользователя

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Protocol Settings
R&S
®
EX-IQ-BOX
191 User Manual 1409.5570.32 ─ 05
The graph in the AxC Container Definition shows the distribution of the data in the CPRI
frame slots.
Argument
Let us prove that using the formula:
   








  
OffTime OnTime
OnTime Cs AssignedAx
solution Re Q / I MHz . s / Mbit Rate Data
assigned
2 84 3
       
s / Mbit . bit MHz . s / Mbit DataRate
assigned
4 358
36
35
3 16 2 84 3
     
7.2.9.3 Low Level BER Test
In section Low Level BER Test , you can check the data transmission in the Rx path of
the CPRI link, provided "Signal Output > BER Test" is set. The Bit-Error-Rate function
evaluates the bit error ratio with a defined data sequence.
Therefore, the PRBS AxCs of the uplink and downlink must be identical regarding "Pat-
tern Length" and position, defined with "Word Addr." and "Bit Addr.".
► To process the "Low Level BER" test, select "Tx Source > PRBS" , and "Rx Signal
Output > BER Test".
Depending on the Test mode,
​
"Physical Source" on page 173 "(Tx)", and
​
"Signal
Output" on page 174 "(Rx)" are given in the corresponding downlink and uplink tab.
The position and the length of the downlink and uplink AxCs must be identical and the
CPRI line must be looped back, e.g. in the DUT.
CPRI