GovTest Government Test & Measurement Business & Procurement » Travis Wheeler

iOS spectrum analyzer lights up with WiFi

Travis Wheeler — Tue, 31 Jan 2012 21:47:07 +0000

Oscium, the company that developed an iOS oscilloscope, has added a spectrum analyzer/power meter for WiFi frequencies. The WiPry isn’t a general-purpose spectrum analyzer because it’s frequency range is limited to the wifi band: 2.4 GHz to 2.495 GHz. It’s available as a spectrum analyzer only ($99.97), an RF power meter ($149.97), or a combination of both ($199.97), which was the unit I tried. See a video of the WiPry in action.

The WiPry’s primary purpose is to help you troubleshoot interference on your wireless network from interference. It lets you see the signals on each of the 13 Wifi channels. I tested the WiPry at home, where my computer detected 11 wireless networks-and that’s with my closest neighbor’s wireless router turned off because the house is vacant during renovations.

Like its oscilloscope cousin, the WiPry attaches to its host directly through its I/O connector. While that’s convenient, it feels kind of weak and could break unless you take care of the system. I’d rather have an extension cable. But wait, Apple’s extension cable won’t work because it extends the power only.

As a spectrum analyzer, the WiPry will show you the activity in the WiFi band. It offers two displays, a “real wave” and a waterfall. The real wave is just what you’d expect, peaks appear whenever a wireless devices transmits (Figure 1). But, those peak some in short bursts and are difficult to capture. Fortunately, the WiPry has a persistance feature that holds the peaks for a few seconds. The waterfall display lets you see the density of the signals as they scroll across the screen. But, the points are difficult to see in the default colors, but yo ucan change them to improve visibility (Figure 2). My home wireless router uses channel 6 and that’s apparent from the waterfall display.

The WiPry screen lets you highlight any of the 13 wifi channels. Simply tap the “+” sign in the screen’s upper left corner. That lets you see the bandwidth of each channel and how the channels overlap (Figure 3). You can also highlight any of the WiFi channels by touching any of the channel buttons (Figure 4) and then touch outside the highlighted channel to see another channel. The video demonstration lets you see that in action.

Digital instruments are great at capturing screens for reports. While you can do that by pressing the front button while holding the on/of button, you can also do that with the WiPry software. Just touch the settings icon and the screenshot button to capture the screen. I prefer using the WiPry’s screen capture to the iPad buttons. The WiPry app produced a landscape image, which was easier to read than the portrait image that the iPad produced. You even use the WiPry app to send a e-mail containing the screen. That’s useful when you don’t have a USB cable or access to your computer.

As a power meter, the WiPry can capture bursts of received signals and display them as peak-to-peak, RMS, duty cycle, min, max, and several other measurements. Power bursts appeared randomly and were difficult to capture at first. When they did appear, they would fade in a few seconds, making cursor measurements rather difficult. Touching and holding the pause/play button sets the WiPry for single-shot capture. Then, the image held.

Full article by Martin Rowe, Test & Measurement World

Free 7-day trial on new Agilent MSO9404A 4 GHz, 4 Analog, 16 Digital Channel, Oscilloscope

Travis Wheeler — Thu, 26 Jan 2012 14:33:28 +0000

Agilent’s Infiniium MSO9404A, equipped with a 15″display, comes in a package that is just 9″ (23 cm) deep and weighs only 26 pounds (11.8 kg). This scope is engineered to give you the broadest measurement capability available to meet your needs both today and in the future. 16 digital channels give you insight into timing relationships and allow precise triggering.

Take advantage of optional integrated protocol viewers to quickly isolate physical layer issues causing errors. Customize your toolset with our debug and compliance packages to tailor the scope to your needs.

U.S. Government, military and prime contractor facilities only

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Free shipping to and from your facility

Limited slots available

Open dates and product datasheet

Schedule a free 7-day field trial

Call GSAMart toll free at (888) 665-2765 x3745 or Sign up

Smart devices create opportunities for test vendors

Travis Wheeler — Fri, 20 Jan 2012 18:06:11 +0000

The rapid changes that are taking place in the wireless communications industry are driving growth in the wireless test equipment market. With the growing number of wireless subscribers, smartphones, wireless data services, mobile banking, and social-networking applications, there is a need for increased functionality in test and measurement tools.

The wireless test equipment market consists of signal generators, spectrum analyzers, network analyzers, and telecom and datacom test equipment. The global wireless test equipment market generated revenues of $3.1 billion in 2011 and is expected to exceed $5.8 billion in 2017 with a CAGR (compound annual growth rate) of 11.0% from 2011 to 2017. Numerous factors are contributing to the growth.

As LTE technology moves toward deployment, it brings new challenges, including higher data rates. The volume of mobile data traffic is increasing as a result of several factors: high-speed networks; an increased penetration of next-generation mobile phones (especially smartphones) and connected devices (laptops, netbooks, notebooks, and tablets); and higher-bandwidth-consuming applications and services.

In 2009, the penetration rate of active 3G (and 3.5G) users in North America was 12%, and it is expected to exceed 35% in 2015. Consequently, the demand for 3G-compatible test equipment is expected to increase. Likewise, the demand for QoS (quality of service) and QoE (quality of experience) analysis is increasing as growing mobile data usage creates more traffic on the network.

Smart devices are changing the mix of traffic from mostly voice to integrated voice, video, and data, thus creating a demand for products that can test a network’s performance and capacity along with how well it handles the integrated transmissions. Another issue that is a driver in the market is the need to support mobility across different technologies, from LTE to 3G, and back to 2G.

The rise of location-based services will also drive growth in the test market. A number of enabling technologies come into play for these services, such as WiFi and different satellite technologies beyond the original assisted GPS.

While the telecommunications industry is excited about data rates of 150 Mbps, LTE-Advanced promises 1 Gbps and 100-MHz bandwidth. The increases in data rates and bandwidth will drive more demand for wireless test equipment for mobile devices and base stations. T&MW

Full article by Olga Yashkova, T&M World

Test and Measurement: On a growth spree

Travis Wheeler — Fri, 30 Dec 2011 17:11:52 +0000

In today’s world of communications, technologies are evolving at a much faster pace, consumers are becoming demanding and there is a strong need for reducing the time-to-market. Along with the quick evolution of technologies, the need of the hour is co-existence of these technologies with better functionality, where test and measurement (T&M) companies play a very crucial role in this dynamic scenario. T&M assures the efficacy of a technology and it vividly defines a roadmap of technologies with an emphasis on the future readiness. After discovering/inventing a technology in any and every segment it is equally important to evaluate its performance before its deployment. As the telecommunications sector ascends the impressive growth curve alongside the emergence of umpteen technologies, T&M is gaining more and more prominence. There is a tremendous demand for conformance and interoperability testing between hands.

Growing Manifold

T&M is growing manifold to date because of the constantly rising subscriber base, higher penetration of technology particularly wireless technologies-LTE, WiMax, BWA, need for QoS, and emphasis on the local manufacturing. Speaking about the T&M dynamics, Shankar Krishnamurthy, country manager, Empirix India and Sri Lanka/Maldives, says, “From a technical perspective, T&M solutions must evolve to support new network protocols and service delivery methods within a single architecture. Operators who can effectively troubleshoot issues can tightly control costs. Those that can assure a great customer experience will build loyalty.” From a business perspective, operators need greater insight into customer behaviors and application usage to make smarter decisions on infrastructure investments, pricing models, marketing campaigns, and revenue generation programs. M Mombasawala, general manager, applications, Agilent Technologies says, “T&M is imperative in providing validation in all areas of telecom, be it R&D activities from companies like Qualcomm or service provider provisioning from Ericsson or consumption from operators.”

Wireless Technologies

Introduction of third generation technologies, proposed launch of fourth generation technologies like LTE, WiMax, broadband wireless access service; and, with the next-generation technologies, telecom T&M is likely to witness strong demand in the coming years. Large scale deployments of communication technologies need large-scale emulation. In India, we predominantly have 2G networks and 3G networks are overlaid on 2G network and ensuring interoperability and inter-working of this network is of paramount importance. The ability to seamlessly hand over between cells while minimizing the interruption to data throughput needs to be tested and assured as does the ability to hand over between different radio access technologies while maintaining the data connection.
T&M plays a crucial role in 3G services, in all aspects of 3G handset and field testing, including core/access network testing. T&M opportunities are increased with the beginning of 3G BTS manufacturing by network equipment manufacturers and 3G handset manufacturing. 3G handset testing and mobile application testing would fall into the testing menu of the SPs. Radio frequency measurements for spectrum clearance, coverage, and interference are a must do to ensure better 3G services. “The adoption of 3G and BWA offer tremendous opportunity. As they add new technologies, operators must include a plan for assuring them. However forward-thinking operators are taking a more strategic approach. Rather than simply installing a new probe to analyze the latest 3G protocol, these operators are choosing a holistic end-to-end T&M solution with predictive capabilities that preempt issues from impacting customers. This assures a better customer experience with significantly reducing the overall cost of troubleshooting and maintaining the network as a whole,” points out Shankar Krishnamurthy, country manager, Empirix India, Sri Lanka/Maldives.

A comprehensive test of radio frequency, protocol and system level elements such as base stations, cell sites, handsets and network infrastructure in a 4G network is a major requirement for its operational efficiency. M Mombasawala, general manager, applications, Agilent Technologies mentions, “A transition to 4G/ LTE greatly increases the complexity of the task of monitoring and troubleshooting mobile data services. Service providers need to develop, deploy and manage the technology in a way that ensures a high QoS while minimizing capex and opex. The latest generation of T&M equipments help to evaluate and deploy equipment that meets specifications and quality standards, verifies new services, and accelerates problem resolution cycle time.” Carriers that get T&M would have many loyal customers on their network for long term. Both fixed and mobile WiMax, a 4G technology, have a very complex requirement in terms of characterization. Conducting a basic RF transmitter measurement on WiMax requires high performance test equipment with advanced measurement functionality. Hence ensuring operational readiness of 4G networks is essential not only during the initial launch of technology but also as network and services grow and mature.

Apart from technologies, there is a dire need to test applications as well. The mobile applications will have to be tested for robustness under bad RF conditions, so as to provide a great end user experience. Besides, enterprise offerings such as cloud computing and virtualizations is also driving T&M. Referring to the T&M requirements Shankar Krishnamurthy says, “End-to-end visibility, regardless of network protocol or service delivery method, is the most important requirement for T&M today. If an operator cannot see the entire communication from start to finish, they cannot understand customer experience, Quality of Service or application performance. If an operator cannot see their entire operations, they cannot assure interoperability, cost-effectively troubleshoot issues or effectively integrate new technologies to optimize the network.”

Increasing Subscriber Numbers

The functionality of T&M tools have been accelerated due to the increasing number of wireless subscribers, increasing number of mobile devices particularly smartphones, a transition from voice to data services including mobile banking, mobile social networking applications, etc.

Service providers ought to ensure better quality of service and experience hence the need to testing has increased. In order to meet the customer expectations, SPs should ensure high quality of network performance thus channel coding, BER, latency, and throughput rates under varying conditions including fading and mobility must be tested.

Full article by Malini N, Voice & Data

How a standard defines a voltage or current pulse greatly influences wave shape

Travis Wheeler — Sat, 17 Dec 2011 18:02:39 +0000

Electronic products must pass some level of immunity tests when subjected to conducted or radiated energy. Some of those tests include subjecting the equipment under test to electrical impulses–short duration single events using defined voltage and current waveforms. Engineers also use impulse tests to verify electrical spacings on PCBs and to periodically check motor-insulation.

Several international standards define impulse waveforms, but only at certain points in how a voltage or current will rise and fall. The waveform shape, peak voltage, impedance, and application of the pulse varies among standards. The test pulse you use depends on the standard you apply because standards define impulses differently.

Waveform Definition

The IEC (International Electrotechnical Commission) has at least two standards that define impulse tests and their waveforms. Use IEC 60060-1, “High Voltage Test Techniques” when testing insulation systems and use IEC 61000-4-5, “Testing and Measurement Techniques – Surge Immunity Test,” for switching and lightning-transient tests. Many standards that define testing of specific products reference either of these two standards because these two standards.

In some end-use Standards, both the insulation system of the DUT (device under test) and the ability of the device to withstand lightning and switching transients are important. The requirements of IEC 60060-1 and IEC 61000-4-5 are different, so the authors of the end-use standard must decide which standard to reference. A relevant example is IEC 61730-2, the Standard for photovoltaic (PV) panels, which references IEC 60060-1 as its impulse standard definition, which is applicable to insulation systems. In the PV standard, the authors note that the test is “To verify the capability of the solid insulation of the module to withstand over-voltages of atmospheric origin. It also covers over-voltages due to switching of low-voltage equipment.” While this scope would be closer to that of IEC 61000-4-5, the authors elected to conduct the test under the requirements of an insulation impulse test, which they deemed a better definition of their test program.

Full article by Jeff Lind, Test & Measurement World

Signal generators and analyzers handle digital modulation

Travis Wheeler — Wed, 30 Nov 2011 17:36:35 +0000

Aeroflex has introduced digital-modulation generators and vector-signal analyzers, all with touch-screen interfaces, to its S-Series line of test instruments. The SDG-3 (3 GHz) and SDG-6 (6 GHz) digital-signal generators include an IQ modulator that lets them generate signals such as QPSK (quadrature phase-shift keying), QAM (quadrature amplitude modulation), and pulse-modulated signals, which are commonly used in wireless communications. The IQ modulator has a 300-MHz RF bandwidth. Both models can produce signals with +13 dBm output power (+20 dBm optional). Both models feature a two-channel AWG (arbitrary waveform generator) with a sample rate of up to 250 Msamples/s and signal memory up to 4 Gbytes. You can use the embedded IQCreator software to generate modulated carriers from the AWG signals.

Both SDG models have low SSB (single sideband) phase noise of -135 dBc/Hz at 1 GHz offset with frequency settling time of 100 μs. The IQ modulators have ACLR (Adjacent Channel Leakage Ratio) of -71 dBc on WCDMA signals.

The SVA vector-signal analyzers also come in two models: SVA-6 (6 GHz) and SVA-13 (13 GHz). You can input signals with peak signal power levels up +30 dBm directly into either instrument. Their maximum sensitivity of -148 dBm/Hz lets you distinguish low-level signals from noise when measuring a transmitter’s spurious outputs. The instruments can measure wireless signals for most wireless standards, including LTE (Long-Term Evolution). Measurements include power, modulation quality, and signal spectrum. Both SVA models have a noise floor of -138 dBc/Hz at 2 GHz with 10 MHz offset and frequency settling occurs in 250 μs at frequencies up to 6 GHz.

When using the SDG and SVA instruments in a single test setup, you can synchronize them so they operate as a single source-and-measuring system. The instruments have a mechanical interlocking system that lets you attach them to each other on a bench or in a rack.

Gigahertz RF measurements can be accurate

Travis Wheeler — Sat, 19 Nov 2011 18:18:11 +0000

Extremely high frequency, which can be defined as the frequencies between 30 and 300GHz, remained relatively undeveloped for many years, except for somewhat esoteric applications such as radio astronomy and remote atmospheric sensing.

That is because this frequency range is highly susceptible to atmospheric attenuation – when resonance of the oxygen molecule attenuates the signal, or when rain absorbs the signal, reducing signal strength.

But with spectrum scarcity in the sub-10GHz band, applications for millimetre-wave systems are found in consumer and non-consumer communications, security, imaging and radar. In particular, with increasing demand for multi-gigabit-per-second communication created by the likes of high-definition (HD) and 3D video, it was soon recognised that the 7GHz of unlicensed bandwidth available around 60GHz was a big opportunity.

So, for several years, the extremely high frequency region has become an area of intense development, with several applications actually being able to capitalise on its signal attenuation characteristics.

Wireless HD

Among the many short-range communications standards that have appeared in the 60GHz frequency range is WirelessHD, a media standard for video in the home that effectively untethers the TV from other home video and audio devices.

Conceived as an in-room, point-to-point, non-line-of-sight standard that uses the band between 57GHz and 64GHz, it is capable of transmitting HD video images and the first products have a limited range of up to10 metres, pleasing copyright owners.

The increased signal attenuation at high frequencies is due to the very small wavelengths generated.

So WirelessHD antennas use various beamforming techniques to concentrate power in the direction of the receiver and bounce signals off nearby objects, using both direct and reflected signals to achieve a stronger, more stable signal.

As you move into higher frequencies and the wavelength size decreases, so the physical structure of devices also comes down in size. This can increase cost dramatically because of the machine costs related to making smaller components. The tolerances involved become much greater too.

Instrumentation can also prove more expensive at higher frequencies, because the frequencies and modulation bandwidth are outside the range of most standard test equipment. One reason for the cost increase is economies of scale.

SiGe and CMOS transistors that can run fast enough for circuits in the millimetre-wave region are a relatively recent arrival, so the growth in millimetre-wave applications has created a correspondingly recent demand for millimetre-wave instrumentation for device specification verification.

Costs can be trimmed by using a down converter module to convert the 60GHz signal to lower frequencies that can be analysed on standard equipment. But there is a risk when using a downconverter or harmonic mixer that the mixing produces multiple image frequencies unsuitable for spurious measurements.

Waveguide flange

Users of harmonic mixers would also need to take account of the waveguide flange, requiring a further conversion to 1.85mm coax to interface with the DUT.

Any additional hardware will also add measurement uncertainty into the signal observed. So it is advisable to use millimetre-wave test equipment that allows measurements to be performed directly on the signal.

When calculating uncertainty in RF measurements stemming from voltage-standing-wave-ratio mismatch, it is important to recognise that uncertainties increase as the frequency rises. So although many spectrum analysers have good power measurement capabilities, a dedicated RF power meter provides better accuracy and impedance matching – critical at higher frequencies.

Precise calibration

It has been said that a vector network analyser (VNA) is only as useful as its measurement accuracy. So to get the best out of a high-frequency VNA, precise calibration is vital. Sources of error come from less than perfect input impedance at the RF receiver and/or output impedance by the RF source, as well as wear and tear to cables and connectors.

Things are further complicated when measurements cannot be made easily at the coaxial connectors, for instance on wafer devices. Calibration won’t fix every error, but you can minimise them by choosing a VNA with good raw system performance and unique calibration techniques.

Full article by Jamie Lunn, ElectronicsWeekly

Manufacturers test new distribution channels

Travis Wheeler — Mon, 07 Nov 2011 18:09:36 +0000

Prominent manufacturers of test equipment, who have historically sold directly to their customers, have begun exploring new sales channels and are now offering a wider variety of products through distributors, franchisees, and online stores. And what may be even more surprising is that their use of these new channels is not limited to low-end instruments. In fact, manufacturers are working more closely than ever with distributors to coordinate both sales efforts and technical support.

“Over the last five years, we’ve seen a major broadening of the channel in terms of the types of equipment that’s resold and the level of sophistication,” said Mike Stonebraker, director of worldwide indirect channels in the Electronic Measurement Group at Agilent Technologies.

Two of the most dominant test-and-measurement companies, Agilent and Tektronix, have both increased sales through distribution. Agilent has honed its distribution strategy over the last two years, a move that appears to be working out well for the company. “It’s been a major trend in our business and a strong contributor to growth as well,” said Stonebraker. Indeed, 25% of the company’s orders come from indirect channels today, compared to only 8% two years ago, according to a company spokesperson.

Stonebraker gave credit to Tektronix and Fluke for pioneering the use of distribution for low-end equipment years ago. Agilent took note of their success, he said, realizing that its customers also likely wanted a more-efficient purchasing process. “Engineers don’t necessarily need to see another engineer to make a decision on what piece of test equipment to buy,” Stonebraker explained. “When a customer wants to buy their 10th scope and it’s exactly like the previous nine, all they want is the quickest and simplest way.”

Tektronix also has expanded its use of indirect channels. The company has used distributors for more than 20 years, but lately has started selling higher-end equipment through the channel. Late last year, Tektronix announced new distribution agreements with Allied Electronics, Entest, Newark, and TestEquity, authorizing those firms to carry higher-performance oscilloscopes, signal generators, spectrum analyzers, logic analyzers, and bit-error-rate testers. And this year, Tektronix, which is a subsidiary of Danaher, inked similar agreements with several European distributors.

Vendors are using specific channels to meet particular needs. Some high-end products are still only available directly from the manufacturer, such as the Tektronix DSA8200 digital sampling oscilloscope, which requires custom configuration, said Gina Bonini, technical marketing manager at Tektronix. On the other hand, some of the company’s distributor partners are beefing up their technical chops and building their own applications teams, she added.
Tektronix direct and indirect sales people frequently work together on sales opportunities, said Faride Akretch, also a technical marketing manager. “We don’t see it as either [a direct sale or an indirect sale]. We see it as a combination of the two.”

Full article by Tam Harbert, Test & Measurement World

High growth market for modular instruments

Travis Wheeler — Thu, 20 Oct 2011 21:34:24 +0000

In industries ranging from aerospace to white goods, the complexity of devices under test (DUTs) is rising, with the devices becoming faster, smaller, and cheaper. This greater product sophistication, along with the incorporation of radio frequency (RF) in an increasing number of devices, is compelling engineers to change their test strategy and adopt modular tools that are flexible enough to be customized to their testing needs. Continued innovations by market majors are helping vendors of modular instruments increase the capabilities of their offerings, thereby driving demand.

Apart from changing the way devices need to be tested, Moore’s Law is improving the functionality of modular instruments. For instance, while RF with PXI was almost an impracticable concept a decade ago, today, RF instrumentation in a small form factor offers very high performance – almost the best in its class. PXI instrumentation has strongly benefitted from technology innovation in semiconductors and more specifically, processors, field-programmable gate arrays (FPGAs), and data converters. Advancements in FPGA capabilities are extremely useful in test and measurement applications, wherein customers need highly deterministic and fast processing capabilities.

Although these product improvements bode well for the modular instruments testing market, manufacturers will be challenged to replace the traditional instruments. While users are expected to gradually shift to modular instruments, they still primarily use traditional rack-and-stack instrumentation due to product familiarity and ease of use. Another important reason for the slow migration is that customers have a wide array of modular instruments to choose from, while with traditional devices, the decision making is far easier as they are closed systems. In 2010, traditional instruments accounted for almost 85 percent of the total market revenue for general purpose test equipment worldwide. Even though its revenue share is decreasing, it will remain a prominent revenue generator in the total market for the next five years.

Increasing automation, superior DUTs, and the hectic pace of research and development (R&D) will swing the revenue balance in favor of modular instruments over time; nevertheless, it will be critical for market participants to educate potential customers about the key benefits of modular instruments over traditional instrumentation.

Full article from Business Wire

Moderate growth predicted for signal generator market

Travis Wheeler — Mon, 10 Oct 2011 18:23:14 +0000

The next 10 years will be a “wireless decade,” as products offering 3G, 4G, and WCDMA wireless interfaces will proliferate. We will see different types of wireless devices beyond the traditional ones, and their fast development and implementation will be the key factor driving the demand for signal generators. It will be imperative for manufacturers of signal generators to adapt their products to comply with evolving wireless standards.

Although the signal generator market has bounced back from the economic crisis of 2009 and is surpassing the levels of 2008, caution and uncertainty continue to restrain end users from making capital expenditures. The industry is demanding products that offer higher performance and higher functionality, yet at a lower cost. In the Asia-Pacific region, the manufacturing base has been increasing and the focus on production has created a much more cost-sensitive environment, boosting the market for signal generators.

Higher bandwidth is the number-one requirement for end users. A greater number of digital modulations transport more data in the same bandwidth, making the modulations more likely to generate imprecise levels of transmissions and phase angles. Signal generators, therefore, play a critical role in test systems. As Bob Buxton, marketing manager in the general-purpose business unit at Anritsu, said, “a signal generator is the heartbeat of the test system; power level is the strength of the heartbeat, accuracy of the instrument is the heart rate, and the quality of the signal is the profile of the heartbeat.” A key driver for vendors of signal generators will be the ability to provide higher frequencies and lower phase noise in their products.

During the economic downturn of 2009, the global revenue for both RF and microwave signal generators declined by an average of 22%. According to Frost & Sullivan’s analysis, the RF signal generator market held the largest market share at 57.3% and is projected to reach $365.8 million in 2011, while the microwave signal generator market accounted for 42.7% of the market and will reach $273.1 million in 2011.

Overall, Frost & Sullivan believes that the signal generator market will experience moderate growth during the forecast period. The compound annual growth rate for RF and microwave signal generators from 2011 to 2015 is estimated at 3.2% and 3.4%, respectively.

Full article by Fernando Nara, T&M World