System-level testing of RF transmitter specifications using optimized periodic bitstreams

In this paper, a novel algorithm has been proposed to measure system specifications of an integrated transmitter, which capture the non-linearities of the system-under-test. The measurement of these specifications is important, as these determine the amount of "interference" created by the transmitting system in adjacent channels while transmitting data in a specific channel. By using an optimized periodic bit stream, with energy concentrated at fewer frequencies, all the specifications of interest are measured. This requires fewer measurements and hence, significantly reduced test time compared to standard test techniques. Studies show that the test time can be reduced considerably by changing the number of periods of the optimum bit-sequence without losing accuracy in measurement. The number of test measurements was reduced by a factor of two. Overall, using the proposed approach, more than an order of magnitude reduction in test time was achieved, while the different specifications were measured up to a maximum accuracy of ±0.2% of the actual value.