A novel data-driven simulation-based diagnostic model is proposed to realize automatic and practical testability analysis (TA) of analog circuits. With this model and the corresponding methods, sufficient faults can be handily injected into the circuit under test and then be simulated to construct the sample data. Using these data, a kernel density estimation on K-nearest neighbors classification algorithm and its leave-one-out cross-validation method are studied to evaluate the testability metrics. To handle the possible high false alarm caused by the faults that have similar samples with the fault-free case, two strategies are carried out by ignoring the faults in the ambiguity groups or/and using the posterior weights to determine the final classification results. Furthermore, a sample compression approach is proposed to reduce the computational cost. Experimental results show that more accurate and reasonable TA and verification can be achieved by comparing with the traditional testability models and the state-of-the-art classification methods. And the diagnostic application against a real circuit based on the simulation data can also reach a satisfactory level.

In this paper, we consider low-complexity design of multi-antenna uplink non-orthogonal multiple access (NOMA) system. There are 2N user equipments (UEs) distributed uniformly in a circle, where the N UEs nearer to the base station (BS) are called strong UEs and the other N farther UEs are called weak UEs. The BS decodes the strong UEs' signals by zero-forcing (ZF) detector first, and subtracts the strong UEs' signals. Then, the BS decodes the weak UEs' signals by ZF detector. For the proposed scheme we obtain the closed-form expressions of the average rate under three scenarios. In addition, a power allocation policy is proposed to reduce the interference between the UEs and maximize the average sum rate. Numerical results verify the analytical results and show that the average sum rate of the proposed NOMA scheme outperforms that of the orthogonal multiple access scheme employing time division multiple access.