• Time Slot Mode available with the MA24x08A, MA24x18A, and MA24126A only.
• Scope Mode available with the MA24x08A, MA24x18A, MA24126A and MA243x0A only
• List Mode available with the MA24208A, MA24218A and MA243x0A only
The power sensor starts up in the Continuous Average Mode (CA Mode) mode after the START command is issued and continuously reads power, except MA242x8A and MA243x0A, which on startup is in RUN state. The CHMOD command is issued to change the sensor’s mode of operation. Mode-specific commands can be issued when the sensor is in any other mode, but will only affect the sensor operation if the sensor is in the mode for which the command is issued. When the sensor mode is changed, the parameters/settings get updated automatically.
CHMOD
Description:
Sets the current power sensor mode and loads related settings except, MA242x8A and MA243x0A, which on startup is in RUN state.
Syntax:
CHMOD <mode> +LF
Return Value:
OK or ERR
Remarks:
<mode> is an integer value as follows: 0 – Continuous Average Mode 1 – Time Slot Mode 2 – Scope Mode 3 – Idle Mode 4 – List Mode
Compatible Sensor
MA24x08A, MA24x18A, MA24126A MA243x0A does not accept 1–Time Slot mode
CHMOD?
Description:
Gets the current power sensor mode.
Syntax:
CHMOD? +LF
Return Value:
Integer value as follows: 0 – Continuous Average Mode 1 – Time Slot Mode 2 – Scope Mode 3 – Idle Mode 4 – List Mode
Compatible Sensor
MA24x08A, MA24x18A, MA24126A MA243x0A does not accept 1–Time Slot mode
Continuous Average Mode (CA Mode)
CA mode is the default mode of operation. In CA mode, the sensor is continuously triggered and collects data at all times. Capture time is the only parameter associated with CA mode. The sensor calculates one average power averaged over the entire capture time. For example, the MA241xxA sensor for 20 ms of capture time, the sensor collects 2860 samples (with an approximate 142 kHz sampling rate). The CA power is the average of the 2860 samples for each 20 ms time frame. The power can be read using the PWR? command. The related CA mode commands are listed below. For MA242x8A and MA243x0A sensors, the approximate sampling rate is 140 kHz. For 20ms capture time, the sensor collects 2801 samples.
CHAPERT
Description:
Sets the effective capture time (aperture time) for average power measurements.
Syntax:
CHAPERT >capture_time> +LF
Return Value:
OK or ERR
Remarks:
<capture_time>
0.01 to 300 ms (MA241xxA) 0.01 to 1000 ms (MA242x8A) 0.01 to 1000 ms (MA243x0A)
Compatible Sensor
MA24x08A, MA24x18A, MA24126A, MA243x0A
CHAPERT?
Description:
Gets the effective capture time (aperture time) for average power measurements.
Syntax:
CHAPERT? +LF
Return Value:
A float value
Return Value:
An aperture time for CA mode in ms.
Compatible Sensor
MA24x08A, MA24x18A, MA24126A, MA243x0A
Time Slot Mode
Time Slot mode operation is generally useful when doing measurement on slotted TDMA signals like GSM. The Time Slot mode breaks up the measurement in time slots and calculates the average power reading for each individual slot. The Time Slot mode measurement can be continuously triggered, but more often it is internally or externally triggered. Triggering is discussed in Trigger Commands. To set up the sensor in Time Slot mode operation, the following four parameters must be set:
• Number of Slots: The number of slots is the number of time slots in the measurement. There is one power reading for each slot, the power reading being the averaged power of all the samples falling within that slot. The maximum number of slots is 128.
• Slot Width: Slot width is the width of each slot in milliseconds. The minimum slot width is 0.01 ms (approximately one sample) and the maximum slot width is 100 ms.
• Start Exclusion: Start exclusion is the time in milliseconds that is excluded from the beginning of each slot for power calculation.
• End Exclusion: End exclusion is the time in milliseconds that is excluded at the end of each slot for power calculation.
Note
Slot Width x Number of Slots = Total Capture Time. Total Capture Time cannot exceed 300 ms for MA24108A, MA24118A, and MA24126A sensors. Total Capture Time cannot exceed 1000 ms for MA24208A, and MA24218A sensors.
The exclusions should not eclipse the entire slot width. Start Exclusion + End Exclusion must be less than the slot width.
MA243x0A sensors will accept Time Slot mode command and parameter, but will not change anything.
The TSLTPARAMS command sends all of the above parameters at once. The TSLTPARAMS? command receives all of the above parameters at once.
TSLTPARAMS
Description:
Sets all of the Time Slot mode parameters.
Syntax:
TSLTPARAMS <num1,num2,num3,num4> +LF
Return Value:
OK or ERR
Remarks:
The input parameters are comma separated values and must be sent in the correct order as follows: num1: Number of Slots num2: Slot Width num3: Start Exclusion Time num4: End Exclusion Time An asterisk “*” can be used instead of a value if the parameter is not to be changed. For example, TSLTPARAMS 8,20,*,1 updates the Number of Slots to 8, the Slot Width to 20 ms, the Exclusion End Time to 1 ms. The Exclusion Start Time remains unchanged. Returns ERR if the input values are out of range.
Compatible Sensor
MA24x08A, MA24x18A, MA24126A MA243x0A sensors will accept Time Slot mode command and parameter, but will not change anything.
TSLTPARAMS?
Description:
Sets all of the Time Slot mode parameters.
Syntax:
TSLTPARAMS? +LF
Return Value:
Comma separated string with the following four values: num1: Number of Slots num2: Slot Width num3: Start Exclusion Time num4: End Exclusion Time
Compatible Sensor
MA24x08A, MA24x18A, MA24126A MA243x0A will return all zero parameters
Scope Mode
In Scope mode, the sensor acts similarly to an oscilloscope in that it can be used to measure power as a function of time. Two parameters are needed to define the Scope mode operation: the collection period and the number of data points. In Scope mode, the sensor first waits for a trigger. Once a trigger is received, the MA241xxA series power sensor collects data at its sample rate of approximately 140 kS/s for the duration of the capture time. For the MA242x8A and MA243x0A series power sensor, the sample rate is 140 kS/s. This typically results in a number of samples that exceeds the number of data points requested, and individual samples are then averaged together to reduce the data set to the requested number of data points.
Gate and Fence
A gate and a fence can be set up to compute the average power of all the points within the gate. The fence is used to mask the unwanted portion of the gate, but a fence remains entirely within the gate. Any points falling within the fence are rejected for the average gate power calculation. Setting the fence start and fence end to zero disables the fence. The gate can be enabled or disabled as desired by using the gate enable GENABLE command. If the gate is enabled, the average power, maximum power, minimum power and crest within the gate can be queried by using the gate power GATEVALUES? query. All values are based on data points and NOT on the individual raw sample packets in the gate.
Capture Time
The capture time is the total time in milliseconds captured by the sensor in a single run. The maximum capture time is 300 ms for MA24108A, MA24118A, and MA24126A and 1 s for MA242x8A and MA243x0A sensors. The capture time can not be made equal to or less than the negative trigger delay. In case of a conflict between trigger delay and capture time, an error is returned when setting scope parameters.
Number of Data Points
The number of data points can never be set less than the total number of samples. For a given capture time, the lower the number of data points, the more samples that are averaged per point, thus the lower the trace noise. The sensor supports a maximum of 1024 data points for the MA241xxA power sensors if there are enough samples. For example, 20 ms of capture time results in 2860 samples (~142 kHz sampling frequency for MA24108A, MA24118A, and MA24126A and 140 kHz sampling frequency for MA242x8A and MA243x0A sensors.). If there are 10 data points, then each data point contains the averaged data of 286 samples. The entire data point array is read out by the RDBUF command as explained in the previous section. Hence, RDBUF reads out 10 data point values separated by a comma (,).
Gate Start
Gate start marks the start of the gate in milliseconds with respect to the trigger (start of capture). The Gate start value can not be negative and it can not exceed the capture time.
Gate End
Gate end marks the end of the gate in milliseconds with respect to the trigger. The Gate end value can not be less than the Gate start value and it can not exceed the capture time.
Fence Start
Fence start marks the beginning of the fence in milliseconds with respect to the trigger. The fence start must always be inside the gate (unless the fence is disabled by setting both the fence start and the fence end to zero).
Fence End
Fence end marks the end of the fence in milliseconds with respect to the trigger. The fence end must always be between fence start and the Gate end (unless the fence is disabled by setting both the fence start and the fence end to zero). If the fence start value and the fence end value are the same, then the fence is ineffective.
SCOPEPARAMS
Description:
Sets the Scope mode parameters.
Syntax:
SCOPEPARAMS <num1,num2> +LF
Return Value:
OK or ERR
Remarks:
The input parameters are comma separated values and must be sent in the correct order as follows: num1: Data Capture Time; MA24108A, MA24118A, MA24126A maximum 300 ms, MA242x8A and MA243x0A maximum 1000 ms num2: Number of Points An asterisk “*” can be used instead of a value if the parameter is not to be changed. For example, SCOPEPARAMS *,4 updates the number of points to 4, while the data capture time is unchanged. A space is treated as a zero. Returns ERR if the input values are out of range.
Compatible Sensor
MA24x08A, MA24x18A, MA24126A, MA243x0A
SCOPEPARAMS?
Description:
Gets the Scope mode parameters.
Syntax:
SCOPEPARAMS? +LF
Return Value:
Comma separated string with the following two values: num1: Data Capture Time num2: Number of Points
Compatible Sensor
MA24x08A, MA24x18A, MA24126A, MA243x0A
GATEPARAMS
This command sets the gate parameters. The parameters are comma separated in the order: gate start, gate end, fence start, fence end. An asterisk (*) can be used instead of a value if the user does not want to change that parameter.
Description:
Sets the gate parameters.
Syntax:
GATEPARAMS <num1,num2,num3,num4> +LF
Return Value:
OK or ERR
Remarks:
The input parameters are comma separated values (in ms) and must be sent in the correct order as follows: num1: Gate Start num2: Gate End num3: Fence Start num4: Fence End For example, GATEPARAMS 0,20,5,15 updates the Gate Start to 0 ms, the Gate End to 20 ms, the Fence Start to 5 ms, and the Fence End to 15 ms. An asterisk “*” can be used instead of a value if the parameter is not to be changed. Returns ERR if the input values are out of range.
Compatible Sensor
MA24x08A, MA24x18A, MA24126A, MA243x0A
GATEPARAMS?
Description:
Gets the gate parameters.
Syntax:
GATEPARAMS? +LF
Return Value:
Comma separated string with the following four values: num1: Gate Start num2: Gate End num3: Fence Start num4: Fence End
Compatible Sensor
MA24x08A, MA24x18A, MA24126A, MA243x0A
GENABLE
Description:
Enables or disables the gate.
Syntax:
GENABLE <gate> +LF
Return Value:
OK or ERR
Remarks:
<gate> is an integer with the following values: 0 – Disable 1 – Enable Returns ERR if <gate> is out of range or if the gate is improperly set up.
Compatible Sensor
MA24x08A, MA24x18A, MA24126A, MA243x0A
GENABLE?
Description:
Gets the gate enable/disable status.
Syntax:
GENABLE?
Return Value:
0 – Disable 1 – Enabled
Compatible Sensor
MA24x08A, MA24x18A, MA24126A, MA243x0A
GATEVALUES?
Description:
Gets the gate average power, peak power, minimum power, and crest for the most recent scope measurement run (with gate enabled).
Syntax:
GATEVALUES?
Return Value:
Comma separated string with the following four values: num1: Average Power (in dBm) num2: Peak Power (in dBm) num3: Minimum Power (in dBm) num4: Crest Power (in dB)
Remarks:
All return values are based on data points and NOT on the individual raw sample packets in the gate. In case of an error, “e” precedes the output. For example: “e2.453,3.456,5.234,2.435”
Compatible Sensor
MA24x08A, MA24x18A, MA24126A, MA243x0A
List Mode
List mode provides the ability to make measurements for a large number of different setups without having to update the sensor settings each time. The user must load the sensor with a setup file containing a list of frequency (GHz), aperture time (ms), and average count settings using the LOADLIST command where each set of settings corresponds to one measurement setup. The sensor and device-under-test (DUT) are synchronized between setups by handshaking with triggers. Once the process is started with the LISTSTART command, the sensor performs power measurements using the settings defined in the setup file and outputs the results automatically once done. The process can be aborted with any command after sending the LISTSTART command and before the process completes.
LOADLIST
Description:
Initiates the process of loading a setup file for List mode.
Syntax:
LOADLIST <num bytes> +LF
Return Value:
OK or ERR
Remarks:
The sensor must be in List mode (CHMOD 4) for this command to be accepted. Once the LOADLIST command is received, the sensor will expect a handshake to take place. The handshake involves sending the “READY?” command to the sensor to which it will reply “READY”. Once the handshake is complete, the sensor will expect <num bytes> of raw file data in 512 byte strings. The sensor will reply OK after receiving each 512 byte chunk. After processing <num bytes> of file data, the sensor will expect another handshake using the same commands as before.
The sensor must be in List mode and have had a setup file loaded using the LOADLIST command in order for the LISTSTART command to be accepted. Once the process is started with the LISTSTART command, the sensor sets the frequency, aperture time, and average count settings defined for the first measurement in the setup file and then waits for a trigger from the DUT. When the sensor receives an external trigger, it performs a power measurement and then sends a trigger out signal to indicate its readiness for the next trigger. This cycle continues until all the measurements have been taken. The power values of all measurements are output automatically at the end of the process. The process can be aborted with any command after sending the LISTSTART command and before the process completes.