Testing LTE - Where to Begin?

With any new technology one of the greatest challenges for the production engineer is what to test and why. This is particularly troublesome for devices as complex as the modern smartphone or tablet. For LTE, the degree of complexity is unprecedented and to test it all would have devices sitting on the tester all day long.

In production test, the primary goal is to exercise the mobile as much as possible to identify manufacturing defects while minimizing test time. The software and digital designs have been proven during engineering and conformance testing. The digital ICs have already gone through extensive testing during their production processes. Digital failures, when they occur, will typically be catastrophic resulting in the phone not powering up, not producing an output or not being able to receive a signal. They can often best be found through techniques like simple internal power up tests and through the use of checksums without any tester involvement at all. Therefore the optimal production tests focus on physical layer measurements, the area that exhibits the largest degree of variability associated with the manufacturing process.

The following sections discuss testing for LTE and how to optimize testing for physical layer testers such as LitePoint’s IQxstream.