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Oscillation Based Testing (OBT) is an effective and simple solution to the testing problem of continuous time analogue electronic filters. In this paper, diagnosis based on OBT is described for the first time. It will be referred to as OBD. A fault dictionary is created and used to perform diagnosis with artificial neural networks (ANNs) implemented as classifiers. The robustness of the ANN diagnostic concept is also demonstrated by the addition of white noise to the “measured” signals. The implementation of the new concept is demonstrated by testing and diagnosis of a second order notch cell realized with one operational amplifier. Single soft and catastrophic faults are considered in detail and an example of the diagnosis of double soft faults is also given.

Wireless signals often propagate in spaces containing large and small obstacles that affect the quality of such radiation. Obstacles cause a nonnegligible loss of the propagated power. The degradation of the signal quality is described by introducing fading and shadowing effects. A case of a wireless communication system that consists of a macro-level component represented by the selection combiner (SC) and two micro-level components consisting of the maximal ratio combiners (MRC) with [Formula: see text] branches is studied in this paper. The MRC component assumes the presence of a single-base station. The received signal is disturbed by simultaneous impact of the multipath Nakagami-[Formula: see text] fading and gamma shadowing. Consequently, the envelope is described by generalized-[Formula: see text] density function. On the other hand, SC component assumes the presence of two base stations, where the average power of the received signal is described using gamma distribution. The exact closed-form expression is obtained for probability density function of the signal at the output of the system, followed by the corresponding outage probability (Pout). Calculations are depicted graphically expressing influences of different fading values as well as the signal parameters.

Testing switched capacitor circuits is a challenge due to the diversity of the possible faults. A special problem encountered is the synthesis of the test signal that will control and make the fault-effect observable at the test point. The oscillation based method which was adopted for testing in these proceedings resolves that important issue in its nature. Here we discuss the properties of the method and the conditions to be fulfilled in order to implement it in the right way. To achieve that, we have resolved the problem of synthesis of the positive feedback circuit and the choice of a proper model of the operational amplifier. In that way, a realistic foundation to the testing process was generated. A second order notch cell was chosen as a case-study. Fault dictionaries were developed related to the catastrophic faults of the switches used within the cell. The results reported here are a continuation of our previous work and are complimentary to some other already published.

In modern computing technique, calculation of leading zeros in a data represented as strings of digits is used very often. Those techniques require high speed of the circuit, as well as its fast design. In this paper we propose a design of such a counter, which is applicable to data length of w = 4j bits, for 4 < j ≤ 8 . With this solution it is also possible to process longer data, since the suggested technique offers a good modularity. This is very important, considering the current technology scaling trends. In this paper, a delay behavior of the proposed circuit has also been investigated using equations and VHDL simulation based worst-case delay estimation method. The results show a significant improvement of the circuit speed, compared to the known solutions.