Systems

PDFB 3

Parkes Digitial Filterbank v. 3

Capability

Specifications

Block diagram of the PDFB3/APSR system currently under development by the ATNF and Swinburne University. The C and D inputs may be used for real-time interference mitigation system (as drawn) or may be used for an independent DFB system. Input signals are Nyquist sampled with 9-bit precision.

Note: For all fold-mode configurations PDFB4 has the same limiting period, except for the 1024 MHz modes where the limiting period is twice as large.

Configurations

Config file name	BW (MHz)	Nr IFs	Nr Pol	Nr Chan	Nr Bins	Bins/Period	MinPrd(ms)

apsr_1024_2048	1024	2	4	2048	1	1	--

srch_1024_512	1024	2	4	512	1	1	--
srch_256_1024	256	2	4	1024	1	1	--
srch_256_512	256	2	4	512	1	1	--

pdfb3_2048_64_2048	64	2	4	2048	2048	2048	65.60
pdfb3_1024_64_1024	64	2	4	1024	1024	1024	16.40
pdfb3_1024_64_512	64	2	4	512	1024	1024	8.20
pdfb3_512_64_1024	64	2	4	1024	512	512	8.20
pdfb3_512_64_512	64	2	4	512	512	512	4.10
pdfb3_256_64_1024	64	2	4	512	512	512	2.05
pdfb3_128_64_1024	64	2	4	512	512	512	1.03

pdfb3_2048_256_2048	256	2	4	2048	2048	2048	16.40
pdfb3_2048_256_1024	256	2	4	1024	2048	2048	8.20
pdfb3_1024_256_2048	256	2	4	2048	1024	1024	8.20
pdfb3_1024_256_1024	256	2	4	1024	1024	1024	4.10
pdfb3_1024_256_512	256	2	4	512	1024	1024	2.05
pdfb3_512_256_2048	256	2	4	2048	512	512	4.10
pdfb3_512_256_1024	256	2	4	1024	512	512	2.05
pdfb3_256_256_2048	256	2	4	2048	256	256	2.05
pdfb3_256_256_1024	256	2	4	2048	256	256	1.03

pdfb3_2048_512_2048	512	2	4	2048	2048	2048	8.20
pdfb3_1024_512_1024	512	2	4	1024	1024	1024	2.05
pdfb3_512_512_512	512	2	4	512	512	512	0.52

pdfb3_2048_1024_2048	1024	2	4	2048	2048	2048	4.10
pdfb3_2048_1024_1024	1024	2	4	1024	2048	2048	2.05
pdfb3_2048_1024_512	1024	2	4	512	2048	2048	1.03
pdfb3_1024_1024_2048	1024	2	4	2048	1024	1024	2.05
pdfb3_1024_1024_1024	1024	2	4	1024	1024	1024	1.03
pdfb3_1024_1024_512	1024	2	4	512	1024	1024	0.52
pdfb3_512_1024_2048	1024	2	4	2048	512	512	1.03
pdfb3_512_1024_1024	1024	2	4	1024	512	512	0.52
pdfb3_512_1024_512	1024	2	4	512	512	512	0.26
pdfb3_256_1024_2048	1024	2	4	512	256	256	0.52

PDFB3 search mode

Fastest sample rates are provided below for different configurations, number of bits and number of polarisations.

nbits	npol	1024_512 (us)	256_1024 (us)	256_512 (us)
1	1	64	128	64
2	1	64	128	128
4	1	64	128	128
8	1	128	128	128
1	2	128	256	128
2	2	128	256	128
4	2	128	256	256
8	2	128	256	256
1	4	256	512	256
2	4	256	512	256
4	4	256	512	256
8	4	256	512	256

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Keywords for PDFB3

AP_NBAND	APSR: Nr of baseband signals across total bandpass
AP_NBIT	APSR: Nr of bits per datum
AP_NDIG	APSR: Nr of digitiser inputs
AP_PROCF	APSR: Name of processing script file
AP_TLEV	APSR: Interval between auto level setting [s], 0 = off.
CAL	Calibration mode (SYNC, FREQ, EXT1, EXT2)
CDCYC	Calibration duty cycle [%]
CFRQ	Calibration pulse repetition frequency [Hz]
CPHS	Calibration pulse phase [deg]
CPFRQ1	CPSR2: Radio frequency, band 1 [MHz]
CPFRQ2	CPSR2: Radio frequency, band 2 [MHz]
D3_CFG	PDFB3: Configuration file name
D3_FRQ	PDFB3: Centre radio frequency [MHz]
D3_TCYC	PDFB3: Cycle time [s]
D3_TSUB	PDFB3: Subint time [s]
FDANG	Feed angle or Position Angle [deg]
FDMODE	Fixed FA (DISABLED) or fixed PA (CONTINUOUS)
MODE	Observing mode (PSR, CAL, LEVCAL, PSRCAL, SRCHSET, SRCH, SRCHCAL)
PM_FRQ1	PMCTRL: (AFB) Radio frequency 1 [MHz]
PM_FRQ2	PMCTRL: (AFB) Radio frequency 2 [MHz]
RCVR	Receiver (e.g., MULTI, H-OH, 1050CM)
RFF_GAIN	Loop gain for RFI adaptive filter
RFF_TC	Time constant for RFI adaptive filter [s]
RFT3_LEV	Threshold for time-domain RFI clipping [sigma], 0=off
SR3_BTC	Time constant for baseline subtraction in search mode
SR3_DDM	DM for de-dispersion
SR3_DNCH	Number of channels per subband for de-dispersion
SR3_FTMX	Maximum search-mode file size [s]
SR3_NBIT	Number of bits per sample for search-mode data
SR3_NPROD	Number of polarisation products for search-mode data
SR3_NSBLK	Number of samples per block (subint) for search-mode data
SR3_TSMP	Sample time for search-mode data [microsec]
TOBS	Observation time [s]

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Troubleshooting

PDFB3: To restart the bcc processes on pkccc3 (block 2) you can log on and issue the bcckill command (same proceedure as for pkbcc04). To restart the processes on l-bcc06 and l-bcc11 it is currently necessary to log into these as root from pkccc3 and type ``reboot''. A power-cycle of DFB3 will achieve the same result but this is not currently recommended

Pulsar Group