Wireless applications drive the development of test and measurement technology

Test and measurement are an important part of any engineering requirement. As the wireless and communications market develops, old technologies are finding new uses. In particular, the 20th anniversary edition of LabVIEW from National Instruments (NI) and the RSA6100A real-time spectrum analyzer from Tektronix will revolutionize the way we test and communicate.

LABVIEW 8.20

Back in 1976, no one had heard of the concept of virtual instruments invented by NI. When LabVIEW was first implemented on Apple's Macintosh, it caused a great sensation. In fact, Electronic Design magazine published the first version of LabVIEW on the cover of its April 17, 1986 issue. Today, LabVIEW has become a symbol in the industry.

The LabVIEW graphical programming language allows designers to create programs by wiring icons on the screen. These icons are then compiled into code for processing data. NI internally calls this language G language or graphical programming language. This language is based on two basic programming concepts, data flow and structure.

Programming.

The real value of LabVIEW is the ability to quickly develop virtual instruments (VIs) that capture, process, and display measurement data from sensors and other input sources. With LabVIEW and a PC, designers can create their own specialized data capture systems or replace standard test instruments such as digital multimeters (DMMs) and oscilloscopes with a few clicks of the mouse.

Users can capture and display data, analyze, display, and understand it through various arithmetic processing. Then users can exchange data through communication interfaces, networks, or the Internet. In addition, they can also perform various control operations using the output of VI. LabVIEW has gradually become a very useful multi-purpose graphical measurement system in design, prototype creation, and final testing.

Virtual instruments, especially LabVIEW, have completely changed the concept of test and measurement, completely eliminating some independent test instruments (such as audio). Today, LabVIEW can also meet the increasingly difficult wireless test and measurement challenges faced by many organizations.

The latest Modulation Toolkit, version 8.20, integrates a range of software to help you build, simulate, design, and test a variety of communications systems (Figure 1). It includes orthogonal frequency division multiplexing (OFDM) technology being adopted by most new wireless systems (such as 802.11a/g, 802.11n, WiMAX, and the upcoming 4G cellular phone standard). During simulation, users can evaluate parameter changes and test design decisions. Then, signal measurements and bit error rate (BER) tests can be performed using that code and external test equipment.

Some of the special features of the modular tool suite are bit generation (PRBS, Galois PN, Fibonacci PN, etc.), channel coding (Reed Solomon, Golay, Hamming, convolution, BCH), interleavers (block and convolution), and most analog or data modulations. Users can perform various modulation analyses such as rho, DC offset, phase error, four-phase offset, IQ gain imbalance, BER, frequency deviation, burst timing, modulation error rate, and error vector magnitude (EVM). [page]

Additionally, users can add noise (AWGN or phase) and impairments such as DC offset, fading, four-phase offset, IQ gain imbalance, and frequency offset to the simulated channel to evaluate performance. This can then be displayed in one of a number of display formats such as trellis, constellation, and 2D/3D eye diagrams.

LabVIEW 8.20 also includes the FPGA Module, which helps users define custom I/O without being familiar with hardware design or VHDL. The FPGA Wizard automates the development of FPGA code for creating custom, user-defined measurement devices. Users can implement FPGA-based measurement devices on plug-in cards in a PC for fast, low-cost prototyping. Or implement FPGA-based measurement devices in NI PXI modules for production testing. This feature includes IF-RIO (Intermediate Frequency, Reconfigurable I/O), which includes two IF digitizers, two IF generators, and an FPGA that can be programmed through LabVIEW on a single PCI board. With IF-RIO, you can prototype communications systems and then run them in real time on a PC. In addition, the modular tool kit can be used with NI's RF generators and receivers to implement a variety of test instruments up to 2.7 GHz.

Tektronix RSA6100A

All communications and wireless engineers wish they had an advanced spectrum analyzer that they could afford, and the Tektronix RSA6100A real-time spectrum analyzer is an excellent choice (Figure 2). Whether you are testing advanced RF technologies such as software-defined radio (SDR), 4G cellular phones and broadband wireless, multicarrier power amplifiers, radar, or any other communications or wireless device, this analyzer will provide you with many useful new features.

For example, it can accelerate spectrum measurement and display by 48,828 measurements per second, compared to just 50 measurements per second on competing analyzers. As a result, the RSA6100A provides a more complete and precise picture of your signal.

Secondly, the RSA6100’s DPX waveform processing function can make the display more vivid. In addition to traditional display functions, it can also provide brightness and color changes, so users can see transient signals and other signals that are usually not visible on other analyzers.

Signal.

With the help of DPX frequency mask trigger (FMT), users can start measurements based on specific event behaviors or event patterns. Users can also use this feature to capture hard-to-capture anomalies and transient signals, thereby improving productivity and accelerating design and debugging progress.

The basic parameters of the instruments are also impressive. The RSA6100A can provide 110MHz real-time bandwidth and 73dB pure dynamic range (SFDR). The frequency range of the RSA6106A is up to 6.2GHz, and the frequency of the RSA6114A is even up to 14GHz. These are high-priced products, but as they claim, you get what you pay for. The best products can help us achieve the best design faster.