Appendix A
SCPI Command Reference
RFGenerator subsystem
744
4460 GSM System Option and 4468 EDGE System Option
Version 12.20
:RFGenerator:EGPRs:MODulation:CHANnel
:RFGenerator:EGPRs:RFGenerator:EGPRs:MODulation:CS
Description
This command selects the bit sequence to be transmitted by the RF generator in
GMSK mode on the 'encrypted data' positions (see section Timeslots and Bursts for
reference). When
:RFG[:GSM]:MOD:TSEQ:STAT OFF
has been selected, all
148 'useful' bits of a timeslot will be filled with the bit pattern specified with this
command.
PRBS9
stands for a pseudo-random bit sequence. The length of this sequence will be
511 bits ((2 to the power of 9)-1).
PRBS15
is a pseudo-random bit sequence with a length of 32767 bits.
PRBS23
is a pseudo-random bit sequence as well. The length is 8388607 bits.
ALLZero
means that all bits transmitted are 'zeros' (000...).
In case
ALLOne
is selected, all bits transmitted will be set to 'ones' (111...).
ONEZero
stands for a bit sequence starting with a 'one' and continuing with the
inverted value of the current bit (10101...).
DOUBleonezero
will set the bits transmitted to a sequence of double 'ones' and
double 'zeros' (11001100...).
FOURonezero
means a bit sequence starting with four 'ones' and continuing with
the inverted value of the current four bits (111100001111...),
while
EIGHtonezero
means a bit sequence starting with eight 'ones' and con-
tinuing with the inverted value of the current eight bits
(111111110000000011111111...).
Query
The query form of this command will return the current setting. The string delivered
back will contain one of short-form versions of the predefined expressions explained
above.
Example
:RFG:EGPRs:MODulation:BITPattern PRBS15
:RFG:EGPRs:MOD:BITP?
Value returned in this example: "
PRBS15
".
Syntax
:RFGenerator:EGPRs:MODulation:CHANnel <PredefExp>
Parameters
PredefExp
is one of the following predefined expressions:
GSM|PDCH|BPDCh
.
Description
Sets the channel type to be generated.
With the GSM setting, the Willtek 4400 sends an uncoded bit pattern (with or with-
out training sequence).
The
PDCH
setting results in one or multiple time slots with channel encoded Packet
Data Channel data.
With
BPDCh
, time slot 0 contains FCCH/SCH/BCCH/CCCH, the other slots are filled
with PDCH.
Query
The query form of this command returns the current setting. The string delivered back
contains one of short-form versions of the predefined expressions explained above.
Example
:RFG:EGPRs:MOD:CHAN BPDCh
:RFG:EGPRs:MOD:CHAN?
Returns the string
BPDC
.
Syntax
:RFGenerator:EGPRs:MODulation:CS <int1>
Parameters
Valid entries for
int1
are in the range from
1
to
4
. The default is
1
.