K5/VSSP(*) and K5/VSSP32 are high-performance samplers dedicated to a geodetic VLBI system
developed by the Kashima VLBI group of
National Institute of Information and Communications Technology (NICT).
K5/VSSP sampler is a PCI bus board mountable on a motherboard of standard PC
and has a maximum sampling frequency of 16 MHz per channel. Any PC equipped with a K5/VSSP PCI-bus
board can be a VLBI recorder, and the data transfer through the Internet is easily realized.
K5/VSSP32 is a successor to the K5/VSSP, but a USB 2.0 is adopted as an interface with a host PC.
Maximum sampling frequency per channel is increased up to 64 MHz. As both K5/VSSP and VSSP32 units has 4 channel
analog inputs, 4 units can cover 16 channels which is sufficient number of channels in case of geodetic VLBI.
Adoption of USB2.0 interface enables us to use a notebook or laptop PC as a host PC of the sampler.
Thus K5/VSSP32 can be used for a not only a VLBI observation but also a general-purpose geophysical
observation which requires precise time label.
Recently K5/VSSP64 became available to use. It is a scuceessor to the K5/VSSP32 and
has a maximum sampling frequency of 128 MHz per channel. A USB 3.0 is adopted as an interface with a host PC.
|K5/VSSP Sampler Board||K5/VSSP32 Sampler Unit||K5/VSSP64 Sampler Unit|
|K5/VSSP sampler board||K5/VSSP32 sampler unit||K5/VSSP64 sampler unit|
|Sampling frequency (MHz)||0.04, 0.1, 0.2, 0.5, 1, 2, 4, 8, 16||0.04, 0.1, 0.2, 0.5, 1, 2, 4, 8, 16, 32, 64||2, 4, 8, 16, 32, 64, 128|
|Built-in digital LPF (MHz)||----||2, 4, 8, 16, through||2, 4, 8, 16, 32,through|
|Analog Input range||-1V - +1V||-1V - +1V||-0.8V - +0.8V|
|Analog band width of AD converter||100 MHz||300 MHz||1250 MHz|
|AD resolution (# of bit)||1, 2, 4, 8||1, 2, 4, 8||1, 2, 4, 8|
|# of channel per board (unit)||1, 4||1, 4||1, 2, 4|
|Maximum data rate per board (unit)||64 Mbps||256 Mbps||1024 Mbps|
|DC offset adjust||NA||available from a host PC||available from a host PC|
|Reference signals||1PPS, 10MHz||1PPS, 10MHz or 5MHz||1PPS, 10MHz or 5MHz|
|Interface to PC||PCI bus||USB 2.0||USB 3.0|
|K5/VSSP32 has been confirmed its operation on "Debian Linux" (recommended), "CentOS", and "FedraCore".|
|Sampler and Observation|
|K5 <==> Mark5 Format Conversion|
|Install Software Correlator|