IFR's vector modulator converts analog signal generator to digital realm
The 2029, when combined with any analog RF signal source, can output digital signals in WCDMA, CDMA2000, IS-95, GSM, IS-136, and EDGE. It eliminates the need to purchase more expensive signal generators or air interface specific radio test sets, a replacement cost that can be three times the cost of using a 2029 with an analog signal generator. For a factory with 200 analog signal generators in test stands, the savings could easily add up to millions of dollars. The 2029 is also smaller and lighter than radio test sets, ensuring it will fit in test stands where space is at a premium.
The 2029 is ideal for handset manufacturing, although its excellent RF performance makes it an effective solution for testing any digital wireless product, including base station amplifiers.
A key advantage of the 2029 is its capability to switch digital formats instantly. This instant format conversion enables the testing of next-generation wireless formats where wireless devices are designed and upgraded with software, not hardware. The new modular devices, dubbed "software radios," are easily handled by the 2029's flexibility. New wireless formats are simply loaded into memory and are ready to be tested with the same test equipment. It is this amazing flexibility that provides manufacturers with a path to the future of advanced wireless testing. As manufacturers convert factories from older analog formats to constantly evolving digital formats, their manufacturing lines can be converted quickly. The 2029 supports multi-band, multi-mode phones using the same test configuration. This means that the 2029 requires only software upgrades to keep up with changing wireless standards. IFR allows manufacturers to "future-proof" their investment in test equipment.
The 2029 combines three instruments in one: a vector modulator, a best-in-class arbitrary waveform generator (ARB) and an RF level-control system, all with excellent RF accuracy to maximize manufacturing yields. It uses an external analog signal generator as a fixed-level unmodulated source to provide its RF input signal. The output from the 2029 is a digitally modulated carrier. The 2029 provides an economic solution for manufacturing test systems that require the use of digitally modulated carriers, particularly where there is large installed base of analog signal generators.
The 2029 uses an external analog signal generator to a provide a local oscillator input signal, an internal arbitrary waveform generator to generate a baseband IQ drive signal, and an IQ modulator to provide a vector-modulated output signal. The 2029 can provide a variety of modulated carriers, including IS-95, by loading suitable data files into the ARB. The internal ARB can be loaded with customer-defined waveforms. The memory can be segmented to define a number of different waveforms, typically equivalent to 15 different IS-95 signals. This allows the selected waveform to be changed without delay. An RF level control system allows the output to be varied over a wide level range, ensuring that it is suitable for measuring both receiver sensitivity and overload. Excellent RF level accuracy in the output control system and attenuator minimizes uncertainly and maximizes repeatability in manufacturing.
An RF combiner is supplied as an option so that other signals can be combined with the 2029 output, or used to connect measuring devices (power meters, spectrum analyzers). The 2029 has no user interface and is designed for operation via GPIB. An RS-232 port is used for firmware and software upgrades.
The 2029's internal arbitrary waveform generator stores digital representations of waveforms. It has a large memory for storing waveforms - up to 15 waveforms lasting 80ms each - and has a high 14-bit sample rate. The 2029 comes with an ARB packager and loader program that is part of the soft front panel. The packager configures source files into a format readable by the ARB, with additional header information attached. The loader transfers the files into the ARB over the GPIB. This set up allows for flexible file management, maximizes the files that can be stored (the smaller the file, the more that can be stored), and enables fast changeover between files. The 2029's ARB decreases testing time because it runs directly from non-volatile memory, so there is no significant lag time on changing waveform files.
Selected specifications
- Frequency range: 800MHz - 2.51GHz
- RF output resolution: 0.01 dB
- RF level accuracy (CW): ± 0.5 dB from 18°C to 28°C for CW signal levels greater than -110 dBm
- RF level accuracy (modulated): Typically <± 0.15 dB level change from a CW signal level with IS-95 modulation multichannel signal applied, with 14.5 dB crest factor, from the internal arbitrary waveform generator
- Soft front panel is supplied (requires Windows 95/98/NT and a GPIB card)
- Height: 107mm (4.2-in)
- Width: 419mm (16.5-in)
- Weight: 10kg (22 lb)
The 2029 vector modulator is priced at U.S. $15,000. It is available immediately upon receipt of order. The 2029 Option 1 RF combiner is priced at U.S. $800. The 2029 can be used with any commercially available RF signal generator. Recommended IFR signal generators for use with the 2029 include the 2023/25, 2026, 2030, and 2040 series. The prices for these products range from U.S. $6,442 to $22,465.
IFR, 10200 West York St., Wichita, KS 67215-8999. Tel: 316-522-4981. E-mail: info@ifrsys.com.
Edited by David Maliniak
Managing Editor, ElectronicsWeb.com