Instruments Meet RF/Microwave Challenges
Striving to meet the challenges of a growing RF/microwave industry, vendors have introduced a variety of instruments and enhancements. “Spectrum Analyzers Get Real” on page 8 provides an overview of the latest in real-time spectrum analysis, and “Vendors Tailor Wireless Test Offerings” on page 18 describes some specific wireless test applications. In addition, just over the past month or so vendors have highlighted new and enhanced spectrum and signal analyzers, signal generators and synthesizers, and power sensors.
For example, Boonton, a Wireless Telecom Group company, recently introduced the 55 Series Wideband USB power sensors. The new line enables high-performance, real-time testing of wideband signals up to 40 GHz. Boonton said its Real-Time Power Processing technology eliminates the acquisition latency associated with traditional peak power meters and sensors. It is suitable for laboratory or field use with applicability for wireless and telecom signals or radar work.
“Advanced modulation schemes and broadband signals created in pursuit of more bandwidth-efficient systems have left engineers dealing with complicated waveforms,” said Murat Eron, vice president of engineering at Wireless Telecom Group, in a press release. “Not only does the new USB platform enable real-time scrutiny of rapidly changing RF and microwave signals and their statistics, but it delivers improved precision in time and amplitude.”
Signal Analyzers
Rohde & Schwarz announced it has increased the frequency range of its high-end R&S FSW signal and spectrum analyzer to 50 GHz. The R&S FSW50 (Figure 1) covers the frequency range from 2 Hz through 50 GHz. Using the company’s harmonic mixers, the frequency range can be extended to 110 GHz.
Figure 1. R&S FSW50 Signal and Spectrum Analyzer
Courtesy of Rohde & Schwarz
In addition, Rohde & Schwarz is doubling the analysis bandwidth of the R&S FSW50 from 160 MHz to 320 MHz. This value allows the demodulation of wideband signals such as radar chirps up to 50 GHz. In the past, measuring these kinds of wideband signals often required complicated test setups consisting of a digital oscilloscope and a downconverter.
Featuring wide RF dynamic range, high measurement speed, and numerous measurement functions, the R&S FSW50 is suitable for use in industrial and university R&D laboratories. The low DANL of -164 dBm/Hz in the microwave range with activated preamplifier allows even the smallest of spurious emissions to be detected—such as those found in radar signals.
The integrated multistandard radio analyzer function of the R&S FSW50 makes it possible to measure spectrum and modulation parameters of differently modulated signals, including their correlation in time.
Signal Generators
Rohde & Schwarz also has focused on signal generators. The new R&S SMW200A high-end vector signal generator combines a baseband generator, an RF generator, and a MIMO fading simulator. The vector signal generator covers the frequency range from 100 kHz to 3 GHz or 6 GHz and features an I/Q modulation bandwidth of 160 MHz. The instrument is suitable for developing high-end components, modules, and complete products for wideband communications systems such as LTE-Advanced and WLAN IEEE 802.11ac.
The R&S SMW200A can be equipped with an optional second RF path for frequencies up to 6 GHz and a maximum of two baseband and four fading simulator modules, giving users two vector signal generators in a single unit. Fading scenarios such as 2×2 MIMO, 8×2 MIMO for TD-LTE, and 2×2 MIMO for LTE-Advanced carrier aggregation can be simulated easily—without complex setups consisting of multiple instruments.
Agilent Technologies has introduced several key enhancements to its high-performance MXG and cost-effective EXG X-Series vector signal generators. The enhancements are designed to improve measurement accuracy, accelerate research and development, and provide in-depth signal simulation for comprehensive receiver verification. These enhancements, coupled with the performance of Agilent’s X-Series signal generators, make these systems suitable for component and receiver development in radar, military communications, and consumer wireless applications.
“The ongoing innovation and performance realized in our X-Series signal generators further strengthen our technology leadership in this market and reaffirm our commitment to meeting the needs of customers testing the highest performance devices,” said Andy Botka, vice president and general manager of Agilent’s Microwave and Communications Division, in a press release. “Our new enhancements build on this commitment by enabling our customers to do their jobs better, faster, and more effectively.”
The enhanced MXG and EXG X-Series RF vector signal generators allow users to apply channel corrections directly to their fixtures and devices under test. A proprietary ASIC, in concert with an Agilent USB power sensor, enables automatic amplitude and phase flatness corrections or equalization. This capability serves engineers working on WLAN 802.11ac or LTE-Advanced transceivers and components.
Two new X-Series connectivity options enable realistic complex-modulated direct digital stimulus (output mode) and digital upconversion (input mode) using an N5102A digital signal interface module. This DSIM enhancement allows users to employ realistic complex I/Q waveforms, which in turn enables faster verification of FPGA algorithms or digital-to-RF performance. It also helps minimize redesign by catching baseband subsystem problems earlier in the design cycle.
A power servo enhancement speeds verification by allowing automatic leveling for external RF amplifiers. The alternative—manually adjusting output power in the amplifier’s nonlinear range—is both tedious and time consuming. With the power-servo enhancement, users can quickly ensure they are at the exact power required for making power-sensitive measurements like error vector magnitude.
In-depth signal simulation solutions provided by Agilent X-Series signal generators now enable comprehensive receiver verification. Agilent’s new N7620B Signal Studio software for pulse-building connectivity, for example, features robust radar verification tests designed to minimize field testing and offer highly accurate characterization. Users can leverage the X-Series’ advanced sequencing engine to obtain realistic 500-s radar antenna scan patterns.
Synthesizers
The distributor Saelig now offers the APSYN420B, a wideband, fast-switching, low phase-noise 0.65-GHz to 20-GHz frequency synthesizer from Switzerland-based AnaPico AG. The synthesizer supports a resolution of 0.001 Hz and phase resolution of 0.1° and has a nominal output power of +13 dBm into 50 Ω. The module features a high-stability internal reference, which can be phase-locked to a user-configurable external reference or used in a master-slave configuration for highest phase coherence. The APSYN420B offers USB and LAN interfaces and can be controlled using an SCPI 1999 command set.
Key features of the APSYN420B include low phase noise, fast switching (settling time is typically 20 µs with a frequency update rate of 200 µs), low phase noise, and an internal OCXO reference that can be configured for high phase coherence between multiple sources. Powered from an external 6-VDC supply, it consumes less than 10 W.
Modulation capabilities are angle, pulse, pulse train, and pulsed chirp. Linear, logarithmic, or random frequency sweeps can be performed with combined modulation running.
Past and Future Events
Finally, Copper Mountain Technologies highlighted its R54 vector reflectometer for cable and antenna testing at the 2013 International Wireless Congress and Expo last March in Las Vegas. The R54, which was connected to a 10-foot coaxial cable, performed a distance-to-fault measurement, detecting a specially placed crimp in the cable.
PLANAR R54 is a vector reflectometer designed for s11 parameter measurement. It provides high accuracy measurements for magnitude and phase in frequencies between 85 MHz and 4.2 GHz. The unit weighs 8.8 oz and has a variety of analytical capabilities in the frequency and time domains.
You can expect Copper Mountain Technologies as well as Agilent, Boonton, Rohde & Schwarz, and many other test-and-measurement vendors to highlight additional new products and enhancements at the International Microwave Symposium June 2-7 in Seattle.