| 摘要 |
PROBLEM TO BE SOLVED: To provide a receiver that reduces the current consumption, enhances the communication speed with an inexpensive configuration of a reduced circuit scale and prevents malfunction due to a steady-state noise at the same time. SOLUTION: A transistor detection circuit 15 provided with a transistor(TR) 15a receives a reception signal by a reception antenna 13 through a preamplifier circuit 14 employing a TR 14a for its amplifier element. A base band amplifier circuit 16 whose amplifier element is a TR 16a receives a detected output of the transistor (TR) detection circuit 15 through a coupling capacitor 24 and gives its amplified output to a comparator circuit that extracts code information from the received signal. TRs with high transition frequency are adopted for the TRs 14a, 16a, which obtain a gain of about 30 dB or over for a frequency band where the carrier frequency of the received signal is in the order of 100 kHz even when a collector current is set to be several microamperes. |
