mm-Wave Phased Array Testing: The Flow From Initial Debug to High Volume Production
Verifying mm-wave product performance has been an industry challenge since the first E-band transceivers were introduced in the early 2000s, although significant progress has been made since then. While sophisticated rack-and-stack mm-wave test and measurement equipment are commercially available today and used to characterize/debug initial engineering samples, mm-wave production testing is still a bottleneck to enable mass production of those products. Test methods and processes need to evolve to cover the new mm-wave requirements while maintaining cost-effectiveness. New phased array multi-RF channel designs of 16, 32, 64 or more antenna elements impose new challenges to test equipments ranging from electrical specifications to mechanical requirements. New specifications, such as accurate phase measurement between antenna ports, require new test hardware architecture and measurement methodology compared to traditional RF and mm-wave transceiver tests. The higher BW is the main advantage of moving to mm-wave frequencies to achieve higher data rate but this requires higher instantaneous analog bandwidth and complex modulation schemes to be measured during test. Test hardware proximity to the handler and prober environment is critical to minimize path losses. Testing modules with an integrated antenna in a production environment requires a completely new thinking, where only over-the-air communications between the tester and the device-under-test is possible. With this build-out come large and growing concerns about how to adequately and economically test the mm-wave frequency ICs found in diverse architectural style of designs. This talk explores mm-wave phased array IC test challenges and solutions needed in the marketplace today. It highlights and explores possible future solutions used to enable cost-effective mass market production. It will demonstrate the state-of-the-art industrial mm-wave test practices from hardware design to Automated Test Equipment (ATE) and test coverage.