LitePoint Helps Deliver Four-Fold Decrease in Test Time

Voice-controlled instant, wireless voice communicator

"Our main goal is to provide a reliable, effective, hands-free WiFi communications device that can be used by a mobile workforce. Our customers won’t settle for clipped conversations or choppy audio. LitePoint testing equipment helps us develop and manufacture high-quality products cost effectively. Having reliable equipment ensures we can deliver a good experience for our customers.”

The Customer

Headquartered in Cupertino, California, Vocera Communications, Inc., has developed a wireless voice communication system to enhance customer service, productivity, and teamwork at hospitals, retail stores, hotels, and service organizations. Using voice prompts, Vocera instantly connects users to the people they need, reducing phone tag, overhead paging, or the need to physically search for a person.

The Need

The Vocera Communications System provides wearable, voice-controlled communication via an 802.11b wireless LAN. It consists of two key components: the Vocera System Software, which controls and manages call activity, and the Vocera Communications Badge, a lightweight, wearable, voice-controlled communication device that operates over an 802.11b wireless LAN.

Initially, Vocera used access points playing as golden radios in their test setup. This worked well with their first chipset, but once they started using other radio chipsets, however, they found incompatibilities that were difficult to identify precisely. By attenuating the signal, their embedded firmware could indicate signal strength bouncing back from an access point, but this method of testing was not particularly reliable.

Vocera looked for a more reliable way to perform 802.11 parametric measurements, thereby improving the overall reliability of the product and customer experience. “Our product doesn’t use the radio chipset the same way as access points, PDAs, or even portable laptops. We can’t afford lost packets during a conversation, because then you get choppy voice audio. If we had data that was shifting a bit or a signal just right on the edge and clipping, that would affect us adversely.”

The Solution

After considering several other devices and finding them difficult to use and implement and less cost-effective, Vocera selected LitePoint. Vocera’s test solution includes LitePoint IQview® 802.11a/b/g/n WLAN R&D Test Solution, an all-in-one test instrument developed specifically for RF testing of 802.11a/b/g/n WLAN products, and IQflex® 802.11a/b/g/n WLAN Mfg Test Solution, an all-in-one test instrument developed specifically for production RF testing of 802.11a/b/g/n WLAN and optional Bluetooth products.

Vocera’s Manufacturing Test Manager, Mike Sweeney, and his team are responsible for manufacturing test development, all manufacturing support, and new product introduction. The team uses LitePoint IQview for test development, running transmit/receive tests in 802.11b and 802.11g modes. LitePoint IQview is also used to measure the EVM percentage, spectral mask, power, and frequency error. For receiver tests, Vocera uses the built-in VSG to transmit custom packets and calculate the PER for unit. A second LitePoint IQview is used to conduct compatibility testing with other devices. Replacing their “ad hoc” testing approach, the LitePoint IQview with its ability to make precision measurements provides real, quantifiable information that helps the team identify potential problem areas.

LitePoint IQflex is used on all final test stations to test 100% of all products – thousands per month – manufactured at Vocera’s contract manufacturer. Each piece gets tested to the radio transmit/receive parameters. Interestingly, the contract manufacturer need not know anything about LitePoint testers; Sweeney’s team has fully automated the test process by designing computer-controlled, custom test fixtures that have been deployed at the manufacturing facility. LitePoint IQsignal Analysis Software Suite, which is included with LitePoint IQview, is used in production with the API and in development to capture and generate packets, allowing Vocera to conduct any custom analysis, capture it, and work with engineering to refine testing.

The Benefits

Faster Test Time Boosts Manufacturing Capacity and Lowers Manufacturing Cost. As Vocera continues to ramp its manufacturing capacity, test times become increasingly critical. “We pay by the minute for contract manufacturing, so speed is important,” says Sweeney. “Our original methods of capturing data and making measurements took from 30 to 40 seconds per unit. With the LitePoint testers, it takes less than ten seconds. As our volume increases, this will really make a difference for us. We can mitigate possible capacity issues by scheduling more time or adding another tester.”

Greater Testing Accuracy Means Fewer Product Returns. Currently, Vocera has four LitePoint IQflex products and two LitePoint IQview products, which makes it easy to test several thousand units a month. Higher quality means fewer returns. Thanks in part to these more accurate testing procedures, Vocera has cut its return merchandise authorization (RMA) rate in half. “Our engineers like these testers because they give them useful, quantifiable information. We’re able to see where problems are and make corrections. We also can make significant design changes for better responses to other chipsets. LitePoint is improving accuracy in test coverage, leading to fewer returns.”

Versatile, Cost-Effective Testing Platform Requires Minimal Maintenance. Sweeney says the LitePoint equipment is easy to maintain with a simple and straightforward annual calibration. “LitePoint IQflex is a cost-effective tool that supplies consistent measurements and helps us to quickly identify problems, while LitePoint IQview gives us an easy method of developing tests to interface with our software. Reliability-wise, the product has been rock solid.” Vocera anticipates using LitePoint to test additional applications and devices in the future. LitePoint spends significant resources writing test programs for specific chipsets, working closely with chipset manufacturers. Vocera is currently evaluating LitePoint IQfact Production Test Software, which would eliminate Vocera’s need to write their own test program.