Earlier this month, Rohde & Schwarz (R&S) announced that it is collaborating with Dolby Laboratories Inc. to provide audio test technology to Dolby and its licensees. I spoke with Greg Kregoski, R&S business development manager - multimedia & A/V test North America, about the significance of this design win, and the challenges behind it.
To start with, R&S has enhanced its UPP and UPV audio analyzer platforms (see Figure 1 and 2) with firmware that will allow Dolby licensees to perform compliance self-testing. (Dolby requires licensees to pass a compliance test before launching new products.)According to Kregoski, testing will primarily take place on site at the Dolby licensees (who are located worldwide). Dolby will also have their own test set up at their labs as well.
Figure 1: Rohde & Schwarz UPV audio analyzer
The required tests vary depending on the technology being tested. Kregoski explains that the R&S audio test platform will initially support Dolby Digital and Dolby Digital Plus technologies, “We are performing all of the audio tests as specified by the Dolby compliance documents.”
For the past ten years, Audio Precision was the exclusive provider of Dolby compliance test hardware. So, to get involved, Rohde & Schwarz had to get in the door. Then, they had to overcome the technical challenge of translating the texts of large compliance documents into software code to automate testing. “We had to create a new piece of software that we refer to as the Sequencer,” says Kregoski. “The Sequencer was designed to allow us to transpose the Dolby textual instructions to automated software. After we had completed and tested our design we had to work globally with Dolby with bi-directional visits to Munich, Nuremberg and San Francisco.” During testing, the software selects and run the tests required by Dolby for that specific device. All measurements follow Dolby specifications, test routines are carried out automatically, and results and device information are summarized in a test report.
Figure 2: Rohde & Schwarz UPP audio analyzer
The equipment that can be used includes the R&S UPP and R&S UPV audio analyzer platforms. Introduced about eight years ago, the UPV is a top-end instrument with a built-in screen and front panel. The UPV supports most audio testing except for HDMI audio. Introduced about two years ago, the UPP was enhanced last year with an HDMI A/V interface. The UPP is a low cost (under $10,000) audio test platform. Because it has no internal screen or front panel, the UPP is the company’s smallest instrument for this application. Using the same firmware as the UPV, the UPP performs fewer measurements, so it is not suitef for some appliations, such as the complete audio testing of mobile devies. Both the UPV and UPP have built-in computers eliminating, the need for an external computer.
The benefits to this collaboration for Rohde & Schwarz, Dolby Laboratories and its licensees are plentiful. Rohde & Schwarz is a worldwide leader in audio, video and wireless telecommunications testing,and has sales and support locations around the globe. For Dolby licensees, it’s all about choice and being able to select the test platform that best fits their needs. “We’re delighted to be a member of the Dolby compliance test portfolio,” says Kregoski.