摘要:
A detector for indicating reception disturbances during ultrashort wave broadcast reception by demodulating of intermediate frequency signals has a frequency modulated demodulator with a demodulation characteristic line formed so that a controlling region within which the output signal increases with increasing frequency deviation from a carrier frequency extends advantageously over the entire band width of the ultrashort wave intermediate frequency channel and is significantly greater than the maximum frequency deviation of the intermediate frequency carrier modulated with the basic band signal in the frequency, and the output signal of the frequency demodulator is supplied to an evaluating circuit at whose output the exceeding of a predetermined frequency disturbance deviation threshold is indicated by a logic signal.
摘要:
An antenna diversity system for the mobile reception of frequency-modulated oscillations having a receiver, antennae and a diversity processor. An optimum system according to the invention includes an FM tuner with intermediate frequency part (2) and at least two antennae, while the diversity processor (3) receives an intermediate frequency signal or high-frequency signal, which corresponds to a given linear combination derived from the antenna signals. The diversity processor (3) further includes an FM demodulator (32) with a succeeding frequency sweep threshold detector (31) and a device by which, in dependence upon the occurrence of an interference-dependent frequency sweep pulse exceeding the frequency sweep threshold of the frequency sweep threshold detector (31) in the intermediate frequency of high-frequency signal, another linear combination derived from the antenna signals is supplied to the input side of the tuner with intermediate frequency part (2).
摘要:
A detector for indicating reception disturbances during frequency modulated ultrashort wave broadcast reception, particularly in power vehicles, has a detector for indicating frequency disturbance deviations in high frequency or intermediate frequency carriers and an amplitude modulation detector for indicating disturbance amplitude modulation in the high frequency or intermediate frequency carrier, and an evaluating circuit with two inputs arranged so that the output signals of the detectors are supplied to the respective inputs of the evaluating circuit and an output signal of the evaluating circuit depends both on the disturbance amplitude modulation and the frequency disturbance deviation.