X-Series Signal Analyzers (MXA/EXA) Single Acquisition Combined Fixed WiMAX™ Measurement Application (N9074A-XFP)

The Keysight Technologies, Inc. N9074A-XFP single acquisition combined Fixed WiMAX measurement application is a breakthrough, high-speed manufacturing test solution available as an option on Keysight’s highest speed mid-range, general-purpose X-Series signal analyzers— the MXA (N9020A) and EXA (N9010A). 

Features and Beneits 

• Supports IEEE standard 802.16d (802.16-2004) 
• Supports demodulation of uplink and downlink signals using IEEE 802.16-2004 modulation formats including BPSK, QPSK, 16QAM and 64QAM 
• SCPI1-based measurement application allows production familiar remote programming commands for ease-of-test software development 
• Flexible selections of predeined parameters allow easy and customizable set-up of the measurements to suit various production test requirements 
• Varied measurement methods to meet different needs for best speed or best accuracy 
• Supports frequency hopping for broadband and multi-frequency points measurements 
• Tabular user interface showing the parameter, measurement, and result lists for easy viewing 
• Parameter list view displays SCPI commands, related parameter name and value in one table and is easier to understand than only showing a list of SCPI commands 
• Additional RF envelope view provides troubleshooting tool for the time alignment between target signal and the instrument  

The increasing complexity of today’s mobile devices, driven by the need for multi-frequency/band coverage, support of multiple formats (2G/3G and emerging communication technologies) and multiple applications (phone, multimedia and PDA) combined with ever-increasing pressure to achieve lower cost factors are driving manufacturers to look for ways to reduce test times and test costs for these complex devices. By using general-purpose RF test equipment without any call-processing for production testing, it is possible to apply new measurement processing techniques to drastically reduce the test time required and keep test costs well under control. The single acquisition combined Fixed WiMAX measurement application allows manufacturers to make measurements much faster than traditional measurements. In the combined measurement applications a single acquisition of data is used for multiple measurements, saving valuable time in comparison to traditional measurements that recapture data for each individual measurement. The N9074A-XFP option is a SCPI-based measurement application with varied parameter setups and a simple user interface. It supports multiple measurements for different signals including frequency hopping signal. The N9074A-XFP option is designed for time-critical tests on the production line, and the high dynamic range of the Keysight signal analyzers ensures that the measurements remain as accurate as possible. 

Advantages of the combined Fixed WiMAX application measurements 

Acceleration of test speed without required measurement switching and using fewer acquisitions Compared with traditional one-button measurements, which limit the “speed” of tests due to measurement switching time (such as from SEM to EVM), the combined Fixed WiMAX measurement application uses SCPI-based programming to configure the X-Series signal analyzer to conduct the specified measurements ahead of time, without measurement switching, and with fewer acquisitions that normally would require processing of the data after each capture is completed.  

Available measurements: 

• Transmit Power 
• Transmit Output Spectrum 
• Modulation Accuracy

 Measurement overview 

The N9074A–XFP combined Fixed WiMAX measurement application is ideal for characterizing the overall PHY layer performance of a Fixed WiMAX signal. Take advantage of standardized tests to evaluate a transmitter against the IEEE standard for manufacturing test. The N9074A–XFP combined Fixed WiMAX measurement application provides all of the IEEE 802.16d Fixed WiMAX transmitter tests. Through SCPI commands, turn Transmit Output Spectrum measurement and Modulation

Accuracy measurement On or Off to assure complete assessment or perform only a few tests to reduce overall test time and speed device evaluation. The Transmit Power measurement specifies the total power of the transmitted signal, and the power spectral density is also provided.  Transmit Output Spectrum measures spurious signal levels for up to four (A/B/ C/D) pairs of offsets. The specification called out in the standard is used as the default, however, the profile of the test masks can be changed as required by using related SCPI commands. The Pass/Fail sign indicates the result status for each offset. Modulation Accuracy measurement provides the results of Frequency Error, Symbol Error, RMS EVM in dB, RMS EVM in percent, I/Q Offset, Absolute Spectrum Flatness Minimum Margin, Absolute Spectrum Flatness Minimum Margin Pass/Fail flag, Difference Spectrum Flatness Minimum Margin, and Difference Spectrum Flatness Minimum Margin Pass/Fail flag. Figure 4 shows an example of Modulation Accuracy measurement.  The N9074A–XFP combined Fixed WiMAX measurement application performs capture according to the capture setup, and after the capture is completed, the acquired data is calculated. The burst setup can be modified for different captures, parameters, and measurements by using SCPI commands. If it is a frequency hopping signal, multiple frequencies in the Center Freq of Burst Setup can be specified and the “Suffix”, which is the time interval for frequency or attenuation change needed by the RF front end, should be designated in the capture setup. There are three types of measurement methods—Best Speed, Balanced, and Best Accuracy to meet specific priorities. 

Greater flexibility of measurement setup 

The N9074A-XFP measurement application option provides high flexibility for the setup of combined measurement parameters. Figure 5 shows an example of a parameter list view. Parameter name, with its SCPI command and value, is listed in this view. The list is ordered in SCPI commands and identifying what parameter corresponds to a specific command can be easily found. The value can be verified or modified in three ways—sending SCPI commands, using the menu and front panel keys, or using a mouse and keyboard. This is more convenient than having to access the SCPI programming interface for minor changes.  

Simplified user interface for reduced processing overhead allows for highest speed 

The user interface of the N9074A-XFP measurement application option is designed for maximum efficiency. All of the results listed in the Result List view can be queried by SCPI commands (see Figures 2, 3, and 4). 

Comprehensive user interface for troubleshooting

 For troubleshooting or diagnostic purposes, the N9074A-XFP measurement application option provides a graphical user interface that displays measurement traces. The RF Envelope view is useful for setting time alignment between target signal and the instrument.