Wavecom W74PC V8.7.0 - Manual (Page 334)

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WAVECOM Data Formats WAVECOM Decoder W74PC, W-PCI/e, W-CODE, W-CLOUD Manual V8.7.0
Single channel IQ Packing – SIQP chunk
The information in this chunk is required to parse the data in the SSIQ chunk.
Element Type Description
iIsIQPacked int32 Value 1 for IQ ordering and value 0 for QI ordering. For example: a val-
ue of 1 will indicate that the first sample in the element awIQData of a
SSIQ chunk is an “I” sample.
Sample Rate
– SR__ chunk
Element Type Description
lSampleRate_uHz int64 The number of samples per second that are being recorded by this
channel.
BandWidth
– BW__ chunk
The bandwidth centred about the centre frequency. If the bandwidth is not centred about the centre fre-
quency use the BWOF chunk instead.
Element Type Description
lBandwidth_uHz int64 The bandwidth of the signal in micro Hertz.
Centre Frequency – CF__ chunk
Element Type Description
lCentrFrequency_uHz int64 The centre frequency of the signal in micro Hertz.
dB Full Scale
– dBFS chunk
Element Type Description
fFullScaleLevel_dBm float32 The analogue input level to the ADC in dBm, which will produce maxi-
mum full scale digital samples for the current IQ time data chunk inte-
ger type. eg. If we are using SSIQ chunks, then a dBFS chunk will indi-
cate the analogue input level that will yield a maximum digital sample
swing of +-(2^15-1). Note that this value may be different from the full
scale value of the ADC.
Single channel Short Real data - SSR_ chunk
Data is assumed to be continuous when using this data format, if the data is blocky, an IQDC chunk
should be sent after every block of continuous data. This chunk can be used to send audio data.
Element Type Description
lTimestamp int64 The timestamp is stored as a 64 bit signed number, representative of
the time of capture of the first sample in the chunk block, in microsec-
ond resolution. It is stored as the number of microseconds since be-
ginning of the epoch (i.e., 1st January 1970 midnight).
awRealData int16[length of
real data array].
The length of the
array must be a
multiple of 2.
Real signed int16 short numbers. Note that regardless of the number
of valid bits, the most significant bits in each short should be used.
This allows us to specify the full-scale level without needing to specify
the number of bits. The number of real int16 shorts in the array must
be a multiple of 2.
Single channel Float Real data - SFR_ chunk
Data is assumed to be continuous when using this data format, if the data is blocky, an IQDC chunk
should be sent after every block of continuous data. This chunk can be used to send audio data.