• National Instruments PXI Data Acquisition system that performs system control and all data acquisition functions
• Larson Automation Custom Interface. This performs the electrical interface from the DUT to the instrumentation
• Equipment Rack. This houses all the GPIB test equipment, RF components, DUT interface, and the computer monitor
• RF switching and routing. This routes all the different high frequency and base-band signals to and from the various test equipment
• Custom Software. This ties the system together and provides the user a single 'Virtual Instrument' to perform testing and evaluation.

PXI Data Acquisition System

The PXI data acquisition system contains the system controller as well as modules for controlling instrumentation and performing data acquisition and control.

• NI PXI-8176 controller: using the embedded controller with a PXI chassis, we build up a compact, high-performance PC platform for modular instrumentation.
  • Full 132 Mbytes/s PCI bandwidth; internal PXI trigger bus routing
  • 512 MB SDRAM with upgrades
  • 512 KB advanced transfer cache, maximum
  • 1.26 GHz Pentium III processor o Additional extended I/O interface, such as GPIB and RS-232
• NI PXI-6508 DIO module provides 96 5V TTL/CMOS digital I/O lines for computers. It is utilized for DUT communication and control purpose.
  • 96 static digital I/O lines (5 V/TTL) in 8-bit ports
  • 2-wire handshake capability
  • Known power-up states
  • Unidirectional and bidirectional I/O
• NI PXI-6070E MIO module provides the analog signal I/O. We use it for digital signal TTL level controls and sensor monitoring such as temperature, power, and etc.
  • 2 analog outputs; 8 digital I/O lines; two 24-bit counters; analog triggering
  • NI-DAQ driver software to simplify configuration and measurements
  • NIST-traceable calibration certificate and more than 70 signal conditioning options
• NI PXI-5112 oscilloscope module. This oscilloscope is suitable for collect the base band signals from I/Q ports of the DUT
  • 2 channels, simultaneously sampled
  • 100 MS/s per channel real-time sampling
  • 2.5 GS/s random interleaved sampling
  • 100 MHz bandwidth
  • 8-bit vertical resolution
  • Waveform memory -- 16 or 32 million samples per channel; multiple records up to 65,536 waveforms

Larson Automation Custom Fixture

• Designed to provide a quick and accurate interface to the DUT through a 68 pin PCMCIA style connector and six quick disconnect RF connectors
• DUT is fully exposed to allow probing for troubleshooting and engineering experiments

• Custom Interface Boards (CIBs) provide the interface between the DUT and the instrumentation for control and monitor purposes
• Level shifters translate signals from DUT 3.3v to TTL levels used by test equipment
• Provide high speed burst to communicate to the DUT at up to 80 MHz

• Route digital control lines used to program the DUT SPI interface, set the synthesizer to different carrier channels, frequency bands, and gain levels.
• Analog sensor monitor to monitor detected power level, temperature, and current consumption through shunt resistors
• Route the 10 MHz reference signal between the test equipment and reference for the DUT to support different modes of testing
• Drive the 28V power for the noise source
• Manage and generate trigger signals for the spectrum analyzer and the digitizer to support various measurements
• Drive LEDs on the front panel to provide operator status of DC power

• Route input signals from the signal generator's RF port, I/Q ports, or Noise Source.
• Route out signals to spectrum analyzer, oscilloscope card, or power meter.
• Route the testing path into 3 individual channels on the DUT.

• Convert the differential I&Q signals to coaxial single-ended 50? signals to interface with standard RF equipment
• Convert the coaxial single-ended 50? signals from the test equipment to differential I&Q signals feed the DUT
• High quality shielded cables protect signal loss and distortion at high frequencies
• Power sensor performs the 'self-calibration' on RF path during testing. This allows the operator to dynamically change test conditions without worrying about stored calibration tables
• Splitters, mixers, and filters to condition signals and route to different locations
• RF switch matrix provides high-quality microwave switch working at 5GHz frequency band. Long relay life expectancy is up to 1 million times. Easily removable switches allow reduced mean time to repair during the maintenance.
  • Microwave switches from DC to 6GHz.
  • Female stainless steel SMA connectors.
  • Compact, self-contained, light weight enclosure.
  • GPIB programmable with SCPI command.
  • Quiet, efficient, built-in power supply.
  • Ten SP6T RF Switches
  • Six SPDT RF Switches

Transmission and Reception Switching Control

The test system simulates a closed signal traversal path, transmission and reception paths. The switching path control utility is designed for application level and instrument driver level. Switching path panel reflects the RF design diagram for user to build up the RF testing path. Ascor switch driver panel provides the access to each individual port of every individual switch unit.

On the transmission path, a source generates base band signal, feeding into the wireless product. After the frequency conversion, modulation, and signal processing, the product transmits a high-frequency modulated RF signal to an analyzer, which checks the processing quality

On the reception path, the source generates RF modulated signal. The product takes the signal as input, with the frequency down-conversion, demodulation and signal process, and sends it into the analyzer to check base band signal feature.

The design also provides plenty of intermediate testing points. The signal monitoring paths are convenient to check signal quality after each signal process.

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