Products Highlight Design and Test Link

Agilent, for example, introduced the U2020 X-Series USB Power Sensors (Figure 1), which provide at least 3,500 readings/s, incorporate built-in trigger functions, and offer the capability to operate without a power meter or external power supply. The U2020 X-Series USB peak and average power sensor family includes the U2021XA (50 MHz to 18 GHz) and U2022XA (50 MHz to 40 GHz); they are priced at $6,700 and $7,100, respectively.

Also on display were five new PNA-L vector network analyzer (VNA) models, offering design and manufacturing engineers frequency ranges up to 50 GHz. The new N523xA PNA-L VNAs replace existing N5230C models. The models feature both increased measurement range (5 dBm more output power and 20 dB more dynamic range) and speed (the result of a new synthesizer with faster frequency switching). They also offer an improved user interface with a 24% bigger display. Because the models are 100% compatible with the N5230C PNA-L, no changes to the user’s current test setup are required.

Agilent exhibited a variety of recently introduced products, including a MIMO PXI vector signal analyzer, signal generators, and FieldFox RF Analyzers with options for time-domain and channel-power measurements. And finally, the company demonstrated its EXA Signal Analyzer, which it calls the industry’s most cost-effective millimeter-wave (mm-wave) signal analyzer. It covers frequencies to 44 GHz or, with external mixing, to 325 GHz.

IEEE 802.11ac Support

Aeroflex announced that it has added IEEE 802.11ac capability to its S-Series RF Signal Generator and Analyzer product line (Figure 2) introduced in 2010. Designed for use by engineers in WLAN research, design, and manufacturing, the new 802.11ac capability is available for the SGD RF Digital Signal Generators (Option 119) and the SVA Vector Signal Analyzers (Option 110).

The S-Series product line’s standard features include a wide bandwidth at 200 MHz, level and frequency settling times of 100 µs, and very low phase noise performance (-135 dB/Hz at 1 GHz, 20-kHz offset).

The S-Series’ wide bandwidth is suitable for WLAN R&D. For manufacturing, the fast settling times enable rapid device throughput. Using Aerolock, the S-Series instruments can be locked together to build complex test setups. Two instruments are combined within a width of 19 inches, allowing both transmit and receive functions in one small space.

“The need for increased device speed, data rates, network capacity, and wide bandwidth has put pressure on the instrument’s hardware to maintain modulation accuracy and increased bandwidth. The S-Series is highly accurate and, with 200 MHz factory-calibrated bandwidth, we can easily cover the needs of 802.11ac with plenty of room for future technologies,” said David Asquith, Aeroflex’s product line manager for the S-Series.

The SGD’s WLAN signal generation suite is now updated for 802.11ac, supporting bandwidths of 20, 40, 80, 80+80, and 160 MHz and up to eight spatial streams. Using an embedded version of Aeroflex’s IQCreator waveform creation software, 802.11ac waveforms are quickly created and played from within the signal generator.

Testing 256QAM modulation demands lower EVM within the test system, Asquith said. To achieve low EVM, Aeroflex developed a new type of factory calibration to maintain orthogonality (the 90° relationship between I and Q) as the baseband frequency increases. Aeroflex’s calibration mechanism effectively creates a digital filter that predistorts the baseband signal before it is applied to the IQ modulator. This new method gives the SGD its 200-MHz of factory-calibrated signal bandwidth and enables testing of the very latest wireless devices.

The SVA offers high linearity and low noise, and it includes a built-in spectrum analyzer. The SVA’s WLAN measurement suite with 802.11ac capability features measurement tools enabling analysis of WLAN OFDM, DSSS, and DSSS-OFDM RF signal characteristics in accordance with IEEE 802.11a, b, g, n, and ac. In addition to support for 802.11ac, generic measurement capabilities are included as standard, and a range of optional modulation analysis suites extends measurement support to a variety of communications standards within the same application framework. Measurement capabilities include power, spectrum, and modulation analysis with results displayed in two user-configurable windows.

Noise-Figure Measurements

Anritsu introduced noise-figure measurements for its VectorStar MS4640A and ME7838A VNAs to provide designers, modelers, and manufacturers of RF/microwave amplifiers with a new capability. Steve Reyes, product marketing manager for network analyzers, said Option MS4640A-041 equips VectorStar to be the only VNA family with 70-kHz to 125-GHz noise-figure measurement, enabled in part by a unique receiver optimized for measurements from 30 GHz to 125 GHz.

Noise-figure measurements allow test engineers to determine potential degradation of signal-to-noise ratio from system components in applications including radar, wireless communications, and digital communications. These design engineers often have to balance the conflicting demands of meeting higher performance requirements with lower budgets in shorter times.

The receiver used to perform the VNA-based noise-figure measurements at 125 GHz incorporates a design focusing on improved noise performance and reduced sensitivity-to-source impedance, Reyes said. The result is a robust capability to make high-quality microwave and mm-wave noise-figure measurements on a wide variety of active devices.

For less experienced test engineers, configuring a noise-figure test setup can be particularly challenging. It often is necessary to add pre-amplification and filtering in front of the measurement receiver to ensure sufficient sensitivity to make a quality measurement. If too little amplification is used, there may be excessive jitter from the instrument A/D converter. If too much power or amplification is applied, compression can impact the measurements.

These two constraints form the effective noise-figure measurement range and can limit the flexibility a user has in choosing pre-amps and filters. The MS4640A-041 option takes advantage of the VectorStar architecture to provide a wider noise-figure measurement range and greater configuration flexibility. In addition, Anritsu enables the use of a simple, low-cost termination, rather than a specialized noise source, as part of the cold source noise-figure measurement method. These advantages result in an easier-to-use, more flexible test system. The MS4640A-041 option for noise-figure measurement capability is priced at $15,000. The 125-GHz receiver, Model SM6609, costs $30,250.

In addition, Anritsu demonstrated mm-wave emission testing using its MS2830A Signal Analyzer and BridgeWave Communications’ 80-GHz Wireless Ethernet Bridge. Reyes noted that the cellular industry is adopting E-band (60 to 90 GHz) gigabit data rate radios for 4G/LTE as it looks to solve the backhaul bottleneck challenge.

Anritsu introduced a four-port configuration for its ME7838A VectorStar that extends the VNA measurement system’s capability to 750 GHz and higher. The ME7838A provides R&D engineers designing four-port or differential mm-wave components with the capability to sweep power across a wide range at frequencies up to 750 GHz using external mm-wave modules without the need for manual attenuators.

The company also presented the Site Master S331L Cable and Antenna Analyzer, which serves in the deployment, installation, and maintenance of wireless networks (Figure 3). The S331L, which covers 2 MHz to 4 GHz, performs return loss, cable loss, and Distance-to-Fault (DTF) measurements. It offers a sweep speed per data point of 1.5 ms (typical) to enable easier identification of intermittent problems in real time. The S331L also features a standard built-in power meter.

The instrument provides eight hours of continuous battery life. It is dust and splash resistant, has a backlit 7-inch TFT touch-screen display, and weighs less than 4.4 lb including a battery. It can store more than 1,000 files (representing sweeps, setups, and screenshots, for example) internally on the analyzer. Every Anritsu Site Master S331L also includes SweepMasters DIRECT, a service that allows S331L users to capture, upload, and deliver traces. Site traces can be emailed as links to the stored traces as well as converted to a .PDF report containing plots of the uploaded traces.

The S331L also can be used with Sweep Master Pro, an enterprise-level, web-based line sweep and tracking tool for large multiple cell-site installation and maintenance projects, and Line Sweep Tools (LST), a free PC-based program that increases productivity for users responsible for recording numerous cable and antenna traces daily. The S331L costs $6,750.

Analyzer Options

Rohde & Schwarz highlighted a variety of instrument features at the show. The company said a new R&S FSW signal-analyzer pulse-measurement option (FSW-K6) speeds up analysis of radar systems. In addition, the R&S FSW-K17 option for the FSW enables the signal analyzer to perform group-delay measurements, which traditionally have been carried out using a VNA. Also for the FSW, the company added support for analyzing 802.11ac signals with bandwidths up to 160 MHz.

Rohde & Schwarz also announced enhancement to its R&S ZNB VNAs (Figure 4). The ZNB-K4 software option supports frequency-converter measurements; it includes a graphical wizard that simplifies the setup and execution of complex measurements. In addition, the ZNB-K14 option enables the ZNB instruments to measure intermodulation distortion.

Cascade Microtech was on hand to highlight a variety of wafer-probing capabilities. The company exhibited its InfinityQuad probes, which support four-quadrant probing of a DUT. Cascade described the challenges of small-pad probing that the InfinityProbe devices alleviate; the challenges include large probe-tip to contact area, poor tip planarity, overtravel-to-skate ratios, tip accuracy, high contact resistance on aluminum pads, side skating, and yaw-axis errors. The company also presented an application note that describes N+1-Port SOLT/SOLR calibration for the probes.

Wireless Telecom Group addressed the need for circuit designers to closely examine Vcc and ground architectures as component integration and ultrafast switching increases, causing noise to permeate the power supply. The company’s approach is to use the Noisecom JV9000 Noise Generator to inject clearly defined, repeatable noise levels to Vcc to let engineers study their systems’ noise response.

NMDG targeted nonlinear measurement, announcing the capability to accurately characterize and model the behavior of mixers using the firm’s ZVxPlus nonlinear extension kits for the Rohde & Schwarz ZVA/ZVT Series VNAs. The new capability takes advantage of the extended multiport measurement feature in NMDG’s Integrated Component Characterization Environment (ICE) software. NMDG said its “primary mixer S-functions” model is similar to S-parameter models and can be cascaded with other blocks.

Mesuro representatives also were on hand to highlight open-loop, active harmonic load-pull solutions to support the design and manufacture of RF and microwave devices and amplifiers. The company’s measurement solution integrates patented hardware with its WaveForm Engineering software suite.

Noise XT introduced its NXA Series phase-noise analyzers, which feature a one-box design and a 14-inch touch screen. The instrument is available in 6-, 26-, and 50-GHz versions. The instrument uses a dual-channel architecture to cancel its internal noise.

And finally, Averna was present to showcase its family of RF record and playback systems, such as the RP-5300 multichannel compact RF recorder that captures real-world RF signals with impairments for GNSS and similar applications.

For More Information

Aeroflex
Agilent Technologies
Anritsu
Averna
BridgeWave Communications
Cascade Microtech
Mesuro
National Instruments
NMDG
Noise XT
Rohde & Schwarz
Wireless Telecom Group

Vendors Show Chips and Components at IMS

IC and component makers at the International Microwave Symposium highlighted a variety of devices targeting applications ranging from handsets to test-and-measurement equipment.