Determining ambient noise in a device under test electromagnetic compatibility test environment is presented herein. A method can include determining, by a system comprising a processor via a radio frequency input port of the system, an ambient electromagnetic noise corresponding to the system; and in response to determining, by the system via the radio frequency input port, a radio frequency signature of a device under test, subtracting, by the system, the ambient electromagnetic noise from the radio frequency signature to obtain a normalized value representing an electromagnetic emission of the device under test. In an example, an antenna/coaxial cable has been connected to the radio frequency input port, the ambient electromagnetic noise can be determined using the antenna/coaxial cable, and a radiated/conducted electromagnetic characteristic of the device under test representing the radio frequency signature of the device under test can be determined using the antenna/coaxial cable.

One embodiment provides an apparatus. The example apparatus includes a root mean square (RMS) distortion determination module configured to determine an RMS distortion error and a signal to noise and distortion ratio (SNDR), the RMS distortion error determined based, at least in part, on a portion of a transmitted pulse centered at or near a transmitted pulse maximum amplitude and the SNDR determined based, at least in part, on the RMS distortion error.

A test and measurement system includes a signal creation tool to generate a complex-valued stimulus signal, at least one waveform generator to receive the stimulus signal and produce at least one pair of baseband signals, a test instrument to capture the at least one pair of baseband signals and produce captured baseband signals, a pre-compensation coefficients estimation block to receive the captured baseband signals, characterize the captured baseband signals and to generate pre-compensation coefficients, and a pre-compensation block to apply the pre-compensation coefficients to the complex-valued stimulus signal when there is a device under test. A method of characterizing a test system includes generating a multi-tone stimulus signal, producing at least one pair of baseband signals form the multi-tone stimulus signal, capturing the at least one pair of baseband signals with a test instrument, characterizing the at least one pair of baseband signals to generate pre-compensation coefficients, and applying the pre-compensation coefficients to signals applied to a device under test.

A modular PIM analyzer includes: a first signal amplification module provided with a first signal generator for generating a first frequency signal under control of a first MCU, and a first power amplifier for generating a first amplified frequency signal through the amplification of the first frequency signal under control of a first ALC circuit; a second signal amplification module provided with a second signal generator for generating a second frequency signal under control of a second MCU, and a second power amplifier for generating a second amplified frequency signal through the amplification of the second frequency signal under control of a second ALC circuit; and a triplexer module for extracting a test frequency signal using the first amplified frequency signal and the second amplified frequency signal, transmitting the test frequency signal to a device under test, and receiving a PIM signal being reflected from the device under test

A modular PIM analyzer includes: a first signal amplification module provided with a first signal generator for generating a first frequency signal under control of a first MCU, and a first power amplifier for generating a first amplified frequency signal through the amplification of the first frequency signal under control of a first ALC circuit; a second signal amplification module provided with a second signal generator for generating a second frequency signal under control of a second MCU, and a second power amplifier for generating a second amplified frequency signal through the amplification of the second frequency signal under control of a second ALC circuit; and a triplexer module for extracting a test frequency signal using the first amplified frequency signal and the second amplified frequency signal, transmitting the test frequency signal to a device under test, and receiving a PIM signal being reflected from the device under test.

A system for measuring electrical characteristics of a device under test (DUT) includes a measuring instrument adapted to be connected with the DUT for transmitting tests signals to the DUT, a receiver adapted to be connected with the DUT and arranged remote from the measuring instrument, an optical transceiver having a first coupler electrically connectable with the measuring instrument and a second coupler electrically connectable with the receiver, and a first and second free space transceivers connected to respective couplers by fiber optic cable. The measuring instrument includes a clock signal generated from a synchronization signal. The synchronization signal is converted to an optical signal by the optical transceiver and transmitted from the first free space transceiver to the second free space transceiver. The second coupler converts the optical signal to the synchronization signal and a clock signal of the receiver is locked to the synchronization signal.

One embodiment provides an apparatus. The example apparatus includes a root mean square (RMS) distortion determination module configured to determine an RMS distortion error and a signal to noise and distortion ratio (SNDR), the RMS distortion error determined based, at least in part, on a portion of a transmitted pulse centered at or near a transmitted pulse maximum amplitude and the SNDR determined based, at least in part, on the RMS distortion error.

A method of calibrating parameters for a polar transmitter (Polar TX) system includes receiving phase information derived from transmission information in a Polar TX for producing a radio frequency (RF) broadcast signal. An Inphase local oscillator (LO_I) signal and a quadrature phase local oscillator (LO_Q) signal are derived from a combination of a first signal and the phase information using a digital phase lock loop. A feedback receiver (FBR) receives the RF broadcast signal provided by the Polar TX. The LO_I signal and the LO_Q signal are mixed with the RF broadcast signal to obtain mixer output signals. RF path delay and IQ phase imbalance are concurrently determined as a function of the first signal and of the mixer output signals.

A quadrature demodulator includes a quadrature demodulating circuit configured to generate an analog in-phase signal and an analog quadrature signal based on an output signal of a low noise amplifier, and a controller configured to cause a thermal noise, instead of the output signal of the low noise amplifier, to be input to the quadrature demodulating circuit, when a correction parameter to correct a mismatch between the in-phase and quadrature signals is being calibrated.

A signal power tester in provided. The signal power tester includes at least one interface to communicatively couple the signal power tester unit to a front-haul communication link used for communicating front-haul data to a remote radio head (RRH) having one or more antenna ports. The signal power tester further comprises a programmable processor, coupled to the interface, configured to execute software, wherein the software is operable to cause the signal power tester to do the following: determine a representative segment indicative of a noise floor of a communication signal; determine whether the representative segment meets selected criterion; determine a translation factor for the representative segment; and measure power of the communication signal based on applying the translation factor.