Reference¶

pyrf.devices¶

.thinkrf¶

class pyrf.devices.thinkrf.WSA4000(connector=None)¶

Interface for WSA4000

Parameters:	connector – Connector object to use for SCPI/VRT connections, defaults to a new `PlainSocketConnector` instance

connect() must be called before other methods are used.

Note

The following methods will either block then return a result or if you passed a TwistedConnector instance to the constructor they will immediately return a Twisted Deferred object.

abort()¶: This command will cause the WSA4000 to stop the data capturing, whether in the manual trace block capture, triggering or sweeping mode. The WSA4000 will be put into the manual mode; in other words, process such as streaming, trigger and sweep will be stopped. The capturing process does not wait until the end of a packet to stop, it will stop immediately upon receiving the command.

antenna(number=None)¶

This command selects and queries the active antenna port.

Parameters:	number – 1 or 2 to set; None to query
Returns:	active antenna port

capture(spp, ppb)¶

This command will start the single block capture and the return of ppb packets of spp samples each. The data within a single block capture trace is continuous from one packet to the other, but not necessary between successive block capture commands issued.

Parameters:	spp – the number of samples in a packet ppb – the number of packets in a capture

connect(host)¶

connect to a wsa

Parameters:	host – the hostname or IP to connect to

decimation(value=None)¶

This command sets or queries the rate of decimation of samples in a trace capture. This decimation method consists of cascaded integrator-comb (CIC) filters and at every value number of samples, one sample is captured. The supported rate is 4 - 1023. When the rate is set to 1, no decimation is performed on the trace capture.

Parameters:	value (int) – new decimation value (1 or 4 - 1023); None to query
Returns:	the decimation value

disconnect()¶: close a connection to a wsa

eof()¶

Check if the VRT stream has closed.

Returns:	True if no more data, False if more data

flush()¶: This command clears the WSA4000’s internal data storage buffer of any data that is waiting to be sent. Thus, It is recommended that the flush command should be used when switching between different capture modes to clear up the remnants of packet.

flush_captures()¶: Flush capture memory of sweep captures.

freq(freq=None)¶

This command sets or queries the tuned center frequency of the WSA.

Parameters:	freq (int) – the new center frequency in Hz (0 - 10 GHz); None to query
Returns:	the frequency in Hz

fshift(shift=None)¶

This command sets or queries the frequency shift value.

Parameters:	freq (int) – the new frequency shift in Hz (0 - 125 MHz); None to query
Returns:	the amount of frequency shift

gain(gain=None)¶

This command sets or queries RFE quantized gain configuration. The RF front end (RFE) of the WSA4000 consists of multiple quantized gain stages. The gain corresponding to each user-selectable setting has been pre-calculated for either optimal sensitivity or linearity. The parameter defines the total quantized gain of the RFE.

Parameters:	gain – ‘high’, ‘medium’, ‘low’ or ‘vlow’ to set; None to query
Returns:	the RF gain value

has_data()¶

Check if there is VRT data to read.

Returns:	True if there is a packet to read, False if not

have_read_perm()¶

Check if we have permission to read data.

Returns:	True if allowed to read, False if not

id()¶

Returns the WSA4000’s identification information string.

Returns:	“<Manufacturer>,<Model>,<Serial number>,<Firmware version>”

ifgain(gain=None)¶

This command sets or queries variable IF gain stages of the RFE. The gain has a range of -10 to 34 dB. This stage of the gain is additive with the primary gain stages of the LNA that are described in gain().

Parameters:	gain – float between -10 and 34 to set; None to query
Returns:	the ifgain in dB

locked(modulestr)¶

This command queries the lock status of the RF VCO (Voltage Control Oscillator) in the Radio Front End (RFE) or the lock status of the PLL reference clock in the digital card.

Parameters:	modulestr – ‘vco’ for rf lock status, ‘clkref’ for mobo lock status
Returns:	True if locked

ppb(packets=None)¶

This command sets the number of IQ packets in a capture block

Parameters:	packets – the number of samples in a packet
Returns:	the current ppb value if the packets parameter is None

preselect_filter(enable=None)¶

This command sets or queries the RFE preselect filter selection.

Parameters:	enable – True or False to set; None to query
Returns:	the RFE preselect filter selection state

raw_read(num)¶

Raw read of VRT socket data from the WSA.

Parameters:	num – the number of bytes to read
Returns:	bytes

read()¶: Read a single VRT packet from the WSA.

request_read_perm()¶

Aquire exclusive permission to read data from the WSA.

Returns:	True if allowed to read, False if not

reset()¶: Resets the WSA4000 to its default settings. It does not affect the registers or queues associated with the IEEE mandated commands.

scpiget(cmd)¶

Send a SCPI command and wait for the response.

This is the lowest-level interface provided. Please see the Programmer’s Guide for information about the commands available.

Parameters:	cmd (str) – the command to send
Returns:	the response back from the box if any

scpiset(cmd)¶

Send a SCPI command.

This is the lowest-level interface provided. Please see the Programmer’s Guide for information about the commands available.

Parameters:	cmd (str) – the command to send

spp(samples=None)¶

This command sets or queries the number of Samples Per Packet (SPPacket).

The upper bound of the samples is limited by the VRT’s 16-bit packet size field less the VRT header and any optional fields (i.e. Stream ID, Class ID, Timestamps, and trailer) of 32-bit wide words. However since the SPP must be a multiple of 16, the maximum is thus limited by 2**16 - 16.

Parameters:	samples – the number of samples in a packet or None
Returns:	the current spp value if the samples parameter is None

stream_start(stream_id=None)¶

This command begins the execution of the stream capture. It will also initiate data capturing. Data packets will be streamed (or pushed) from the WSA4000 whenever data is available.

Parameters:	stream_id – optional unsigned 32-bit stream identifier

stream_status()¶

This query returns the current running status of the stream capture mode.

Returns:	‘RUNNING’ or ‘STOPPED’

stream_stop()¶: This command stops the stream capture. After receiving the command, the WSA system will stop when the current capturing VRT packet is completed.

sweep_add(entry)¶

Add an entry to the sweep list

Parameters:	entry (pyrf.config.SweepEntry) – the sweep entry to add

sweep_clear()¶: Remove all entries from the sweep list.

sweep_read(index)¶

Read an entry from the sweep list.

Parameters:	index – the index of the entry to read
Returns:	sweep entry
Return type:	pyrf.config.SweepEntry

sweep_start(start_id=None)¶: Start the sweep engine.

sweep_stop()¶: Stop the sweep engine.

trigger(settings=None)¶

This command sets or queries the type of trigger event. Setting the trigger type to “NONE” is equivalent to disabling the trigger execution; setting to any other type will enable the trigger engine.

Parameters:	settings (pyrf.config.TriggerSettings) – the new trigger settings; None to query
Returns:	the trigger settings

pyrf.connectors¶

.blocking¶

class pyrf.connectors.blocking.PlainSocketConnector¶

This connector makes SCPI/VRT socket connections using plain sockets.

connect(host)¶

disconnect()¶

eof()¶

has_data()¶

raw_read(num)¶

scpiget(cmd)¶

scpiset(cmd)¶

sync_async(gen)¶: Handler for the @sync_async decorator. We convert the generator to a single return value for simple synchronous use.

pyrf.connectors.blocking.socketread(socket, count, flags=None)¶: Retry socket read until count data received, like reading from a file.

.twisted_async¶

class pyrf.connectors.twisted_async.SCPIClient¶

connectionMade()¶

dataReceived(data)¶

scpiget(cmd)¶

scpiset(cmd)¶

class pyrf.connectors.twisted_async.SCPIClientFactory¶

buildProtocol(addr)¶

clientConnectionFailed(connector, reason)¶

clientConnectionLost(connector, reason)¶

startedConnecting(connector)¶

class pyrf.connectors.twisted_async.TwistedConnector(reactor, vrt_callback=None)¶

A connector that makes SCPI/VRT connections asynchronously using Twisted.

A callback may be assigned to vrt_callback that will be called with VRT packets as they arrive. When .vrt_callback is None (the default) arriving packets will be ignored.

connect(host)¶

disconnect()¶

eof()¶

raw_read(num_bytes)¶

scpiget(cmd)¶

scpiset(cmd)¶

sync_async(gen)¶

exception pyrf.connectors.twisted_async.TwistedConnectorError¶

class pyrf.connectors.twisted_async.VRTClient(receive_callback)¶

A Twisted protocol for the VRT connection

Parameters:	receive_callback – a function that will be passed a vrt DataPacket or ContextPacket when it is received

connectionLost(reason)¶

dataReceived(data)¶

eof = False¶

makeConnection(transport)¶

class pyrf.connectors.twisted_async.VRTClientFactory(receive_callback)¶

buildProtocol(addr)¶

clientConnectionFailed(connector, reason)¶

clientConnectionLost(connector, reason)¶

startedConnecting(connector)¶

pyrf.config¶

class pyrf.config.SweepEntry(fstart=2400000000, fstop=2400000000, fstep=100000000, fshift=0, decimation=0, antenna=1, gain='vlow', ifgain=0, spp=1024, ppb=1, trigtype='none', level_fstart=50000000, level_fstop=10000000000, level_amplitude=-100)¶

Sweep entry for pyrf.devices.thinkrf.WSA4000.sweep_add()

Parameters:

fstart – starting frequency in Hz
fstop – ending frequency in Hz
shift – the frequency shift in Hz
decimation – the decimation value (0 or 4 - 1023)
antenna – the antenna (1 or 2)
gain – the RF gain value (‘high’, ‘medium’, ‘low’ or ‘vlow’)
ifgain – the IF gain in dB (-10 - 34)
spp – samples per packet
ppb – packets per block
trigtype – trigger type (‘none’ or ‘level’)
level_fstart – level trigger starting frequency in Hz
level_fstop – level trigger ending frequency in Hz
level_amplitude – level trigger minimum in dBm

class pyrf.config.TriggerSettings(trigtype='NONE', fstart=None, fstop=None, amplitude=None)¶

Trigger settings for pyrf.devices.thinkrf.WSA4000.trigger().

Parameters:	trigtype – “LEVEL” or “NONE” to disable fstart – starting frequency in Hz fstop – ending frequency in Hz amplitude – minumum level for trigger in dBm

exception pyrf.config.TriggerSettingsError¶

pyrf.numpy_util¶

pyrf.numpy_util.compute_fft(dut, data_pkt, context)¶

Return an array of dBm values by computing the FFT of the passed data and reference level.

Parameters:	dut (pyrf.devices.thinkrf.WSA4000) – WSA device data_pkt (pyrf.vrt.DataPacket) – packet containing samples context – dict containing context values

This function uses only dut.ADC_DYNAMIC_RANGE, data_pkt.data and context[‘reflevel’].

Returns:	numpy array of dBm values as floats

pyrf.util¶

pyrf.util.read_data_and_context(dut, points=1024)¶

Wait for and capture a data packet and collect preceeding context packets.

Returns:	(data_pkt, context_values)

Where context_values is a dict of {field_name: value} items from all the context packets received.

pyrf.vrt¶

class pyrf.vrt.ContextPacket(packet_type, count, size, tmpstr)¶

A Context Packet received from pyrf.devices.thinkrf.WSA4000.read()

fields¶: a dict containing field names and values from the packet

is_context_packet(ptype=None)¶

Parameters:	ptype – “Receiver”, “Digitizer” or None for any packet type
Returns:	True if this packet matches the type passed

is_data_packet()¶

Returns:	False

class pyrf.vrt.DataPacket(count, size, streamId, tsi, tsf, payload)¶

A Data Packet received from pyrf.devices.thinkrf.WSA4000.read()

data¶: a pyrf.vrt.IQData object containing the packet data

is_context_packet(ptype=None)¶

Returns:	False

is_data_packet()¶

Returns:	True

class pyrf.vrt.IQData(binary_data)¶

Data Packet values as a lazy collection of (I, Q) tuples read from binary_data.

This object behaves as an immutable python sequence, e.g. you may do any of the following:

points = len(iq_data)

i_and_q = iq_data[5]

for i, q in iq_data:
    print i, q

numpy_array()¶

Return a numpy array of I, Q values for this data similar to:

array([[ -44,    8],
       [ -40,   60],
       [ -12,   92],
       ...,
       [-132,   -8],
       [-124,   56],
       [ -44,   80]], dtype=int16)

exception pyrf.vrt.InvalidDataReceived¶

pyrf.vrt.vrt_packet_reader(raw_read)¶

Read a VRT packet, parse it and return an object with its data.

Implemented as a generator that yields the result of the passed raw_read function and accepts the value sent as its data.