| 摘要 |
PURPOSE: To obtain a receiver for automobile ratio using an uncomplicated inexpensive filter. CONSTITUTION: A radio receiver is provided with a filter BPF, a limiting amplifier SL, a demodulating means DM which reproduces digital signals transmitted at a bit error rate lower than a prefixed error value, when the level of received signals falls within a prefixed dynamic range. The amplifier SL has such an input-output characteristic that the gain is substantially linear with respect to an intermediate input signal, having an amplitude smaller than a prefixed value and decreases towards a limiting value with respect to an intermediate input value having an amplitude larger than the prefixed value. The intermediate input signals, having small and large amplitudes respectively correspond to received signal levels within the dynamic range. |
