Software for a Versatile RF Test
Platform (page 3)
Software development is often the most time consuming task in the development of a new RF test system. One of the great beauties of a general-purpose RF test system is the opportunity to leverage the software development investment across a large variety of RF test applications.
At a high-level our software architecture includes functionality for managing tests, sequencing test steps, interacting with the user and archiving data. The basic software architecture is not limited to RF test as it is general across automatic test equipment.
The following list shows specific modules within the architecture.
• System Calibration Software
• Instrument Drivers
• Data Management
• Limit Checking
• Security Software to enable removal of secure data from system
• Error Manager
• GUI Control
• Instrument Manager
• Manual Control
• Self Test – Loop back
• Self Test - Instrument Built-In-Test
• Calibration Interval Manager
• Bar Code Reader Interface
At the core of our general-purpose RF test software is the following set of standardized tests.
• Transmitter S-Parameters (pulsed or CW): Measure the four calibration-corrected S-parameters at specified frequencies, for either the TX path, with either pulsed or CW. Measure Gain changes versus Phase change correlation
• Transmitter Pulsed Phase Shifter Measurements (RMS and Peak Phase and Amplitude Errors): The phase deltas (relative to default settings) are determined from measurements of S21 at each of the phase states. Additionally, gain change vs. phase state can also be performed
• Transmitter Pulsed Attenuator Measurements (RMS and Peak Amplitude Errors): The amplitude deltas (relative to default settings) are determined from measurements of S21 Additionally, insertion phase change vs. attenuation state can also be performed
• Transmitter Pulsed Compression Measurements: Measure gain compression point of the TX path at specified frequencies.
• Transmitter Isolation: Measure isolation of TX signal to RX path
• Transmitter Gain changes versus Power Supply changes: Measure Gain changes versus power supply changes
• Recovery time: Measure the recovery time of the Receiver upon switching from high power transmit mode
• Harmonics: Measure the output harmonic content
• Spurious: Measure the output spurious content
• Pulse Profile (Pulse Width Variation, Rise and Fall Time, Peak Output Power, Amplitude and Phase Droop and Ripple): A pulsed measurement on the UUT. At each frequency, a number of points are measured for different settings of the gate-to-trigger delay
• Wideband Pulse Profile: A pulsed measurement on the UUT for different settings of the trigger-to-TR Modulation pulse delay.
• Output pulse delay: Measure the time delays from the rising or falling edge of the UUT T/R control line, or from a change in the stepped attenuator setting, to the 50% point of the resulting change in the RF envelope
• Pulse to pulse amplitude and phase stability: Measure RMS pulse to pulse amplitude and phase changes
• Residual output noise: Measure the output noise with no signal applied to the module
• Receiver S-Parameters (pulsed or CW): Measure the four calibration-corrected S-parameters at specified frequencies, for the RX path, with either pulsed or CW
• Receiver Noise Figure: Measure the RX noise figure at the specified frequencies
• Receiver Phase Shifter (RMS and Peak Phase and Amplitude Errors): The phase deltas (relative to default settings) are determined from measurements of uncorrected S21
• Receiver Attenuator (RMS and Peak Amplitude Errors): The amplitude deltas (relative to default settings) are determined from measurements of uncorrected S21
• Receiver ITOI Direct method: Two CW inputs, at frequencies f1 and f2 with equal amplitudes, are applied to the RX input. The output amplitudes at f1 and f2 as well as of the third-order components at 2f1 − f2 and 2f2 − f1 are read and used to compute the third-order intercept in terms of input levels (ITOI).
• Receiver ITOI Modulation-transfer method: A CW signal at frequency f1 and a pulse-modulated signal at frequency f2 are applied to the RX input. The external generator provides f1 and the PNA-X source provides f2 routed through the pulse modulator. The MXA spectrum analyzer is used to read the amplitude of the output f1 sidebands.
• Receiver Cross Modulation: Measure cross modulation caused by interfering signals – internally or externally generated
• TR Module ID: Verifies the unique address(es) programmed into the UUT for TX and RX functions
• TR Module Status: Read module status information
• Output Third Order Intercept: The third order intercept point is calculated from the products generated by 2 frequencies at 2 power levels
• Gain Transfer: This test characterizes the gain transfer curve for a communication channel, along with determining the saturation and gain compression points (expressed in terms of input or output power). In general, this test measures CW output power versus CW input power.
• Frequency Response: This test measures the gain flatness, gain slope and maximum gain slope for a specified frequency interval
• AM-PM Distortion: This test measures the amplitude modulation (AM) to phase modulation (PM) distortion of a carrier through the communication channel. It is typically performed by injecting a signal at the center frequency of the uplink channel.