摘要:
A receiver includes an oscillator for generating a local oscillator signal, a frequency converter for heterodyning a received signal of one frequency band or a plurality of frequency bands into an intermediate frequency (IF) signals with using the local oscillator signal, a filter connected to an output of the frequency converter and having a cut-off frequency changeable, an analog-digital (AD) converter connected to an output of the filter to convert an analog signal of one frequency band or a plurality of frequency bands into a digital signal, a pre-stage detector connected to an output of the AD converter or connected between the filter and the AD converter to detect a signal level, and a controller for controlling the cut-off frequency of the filter based on the signal level detected by the pre-stage detector.
摘要:
A receiver includes an oscillator for generating a local oscillator signal, a frequency converter for heterodyning a received signal of one frequency band or a plurality of frequency bands into an intermediate frequency (IF) signals with using the local oscillator signal, a filter connected to an output of the frequency converter and having a cut-off frequency changeable, an analog-digital (AD) converter connected to an output of the filter to convert an analog signal of one frequency band or a plurality of frequency bands into a digital signal, a pre-stage detector connected to an output of the AD converter or connected between the filter and the AD converter to detect a signal level, and a controller for controlling the cut-off frequency of the filter based on the signal level detected by the pre-stage detector.
摘要:
An OFDM reception device includes: a first channel estimation unit for estimating a channel distortion by using a signal that is supplied from the reception unit and has a first time interval; a second channel estimation unit for estimating a channel distortion by using a signal that is supplied from the reception unit and has a second time interval shorter than the first time interval; a selection unit for selecting and outputting one of a signal from the first channel estimation unit and a signal from the second channel estimation unit, according to a control signal from the control unit; and a correction unit for correcting a reception signal supplied from the reception unit, according to the channel estimation signal from the selection unit. The control unit determines the control signal to be supplied to the selection unit, according a reception state of the reception unit.
摘要:
An oscillator unit is configured such that a frequency adjustment unit of a synthesizer used by a controller is smaller than a frequency variation tracking capability of a demodulator connected to an output side of a frequency converter. This structure successfully combines the temperature compensation control of an oscillator unit and the receiving process of a high-frequency receiving device. Accordingly, an oscillator unit with large temperature coefficient is applicable to high-frequency receiving devices.
摘要:
A receiving apparatus includes a first receiver, a second receiver, a received signal synthesizer connected to the first and second receivers, a synchronizing signal synthesizer connected to the first and second receivers, and a synchronization detector connected to the synchronizing signal synthesizer. In this structure, synchronization determination is performed using a synchronizing signal of either the first or second receiver, and diversity reception is performed using the received signals of the first and second receivers.
摘要:
An oscillator unit is configured such that a frequency adjustment unit of a synthesizer used by a controller is smaller than a frequency variation tracking capability of a demodulator connected to an output side of a frequency converter. This structure successfully combines the temperature compensation control of an oscillator unit and the receiving process of a high-frequency receiving device. Accordingly, an oscillator unit with large temperature coefficient is applicable to high-frequency receiving devices.
摘要:
An oscillator unit is configured such that a frequency adjustment unit of a synthesizer used by a controller is smaller than a frequency variation tracking capability of a demodulator connected to an output side of a frequency converter. This structure successfully combines the temperature compensation control of an oscillator unit and the receiving process of a high-frequency receiving device. Accordingly, an oscillator unit with large temperature coefficient is applicable to high-frequency receiving devices.
摘要:
The demodulator in the receiving module of the invention supplies a signal produced based on a signal level detected by a first detector to a second amplifier as an amplification degree adjustment signal. With this arrangement, when a second receiver works, an AGC voltage supplied to the second receiver is already close to an ultimately converging certain value. The AGC voltage supplied to the second receiver is thus stabilized in its value, from the value close to the ultimately converging certain value to the certain value. Accordingly, a time period required from the second receiver starts working until the AGC voltage supplied to second amplifier ultimately converges into the certain value is shortened.
摘要:
In digital broadcast receiver (100), when a bit error rate (BER) is larger than a threshold in BER determining part (109), power is supplied to tuner (103) and tuner (104) for diversity reception. When the BER is smaller than the threshold, power supply to one of tuner (103) and tuner (104) is stopped for single reception. This structure allows power supply to one of the tuners to be stopped in excellent reception environments, thus reducing power consumption.
摘要:
An oscillator unit is configured such that a frequency adjustment unit of a synthesizer used by a controller is smaller than a frequency variation tracking capability of a demodulator connected to an output side of a frequency converter. This structure successfully combines the temperature compensation control of an oscillator unit and the receiving process of a high-frequency receiving device. Accordingly, an oscillator unit with large temperature coefficient is applicable to high-frequency receiving devices.