JPH05284054A - Remote frequency converting device - Google Patents

Abstract

PURPOSE:To select a receiving frequency at a distant part without interferring received signals even in the case of transmission multicoupling cable wires for transmitting received signals by using two-phase modulated frequency control signals by binary noise. CONSTITUTION:A phase locked loop (t) is composed of a phase comparator 5, filter 6 and voltage (current) controlled oscillator 7 and oscillated while synchronizing the phase to a designated local oscillation frequency simultaneously with the demodulation of two-phase mosulation due to binary noise. Frequency converted signals are transmitted to the main body device by cable wires 8. Since the carrier frequency of the control signal to decide the local oscillation frequency can be set by a designated signal input 18, the receiving frequency of an antenna part can be selected at the indoor device. An intermediate frequency limiting the band is available for the transmitted signals of the cable wires, the quality of received signals is improved as well, and the main body receiver is also simplified. Further, the frequency designating control signals are transmitted to plural antennas as radio waves, and the receiving frequency can be selected as well.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to an antenna and a frequency converter installed in a remote place such as a receiver of a television radio wave by satellite broadcasting, and a signal capable of improving reception performance and highly accurate frequency conversion. The receiver of the present invention.

[0002]

2. Description of the Related Art In a conventional satellite broadcasting television receiver, a radio wave received by an antenna is frequency-converted at a predetermined local oscillation frequency (a reception frequency of 11 GHz is 1.0 GHz).
(Ishi 1.3 GHz band) and transmit through the cable line,
The receiver of the main body performed frequency conversion again to selectively receive the desired signal.

[0003]

In the current frequency converter, the radio waves of several television stations are simultaneously frequency-converted and transmitted at a relatively high frequency in the wide band through a cable line or the like, so that the signal is attenuated. There is a limit on the transmission distance. Further, a frequency conversion circuit that causes deterioration of performance, such as selective reception of a desired signal by an indoor receiving device, is required twice.

[0004]

[Means for Solving the Problems] The oscillation frequency of a local oscillation device existing in an antenna unit is transmitted as a control signal from a main body (indoor) receiving device, and frequency conversion of a desired signal is performed to obtain an intermediate frequency determined by a signal band. The present invention relates to a method of improving reception performance and transmission distance by transmitting. Therefore, one cable line is used to transmit the control signal and the intermediate frequency signal of the received wave in the up and down directions. Further, as a control signal, a signal having a carrier frequency of 1/2 (1 / even number) of the local oscillation frequency is subjected to two-phase (multi-phase) phase modulation by binary noise, the frequency is spread, and the control signal is transmitted by the antenna section. To generate a specified local oscillation frequency.

[0005]

[Function] The carrier is subjected to two-phase (multi-phase) phase modulation by binary noise to form a wide band low level spread spectrum signal,
It is transmitted as a control signal that does not interfere with others. On the receiving side, it is possible to demodulate a carrier frequency that is double (even number) by a squaring circuit or a multiplying (even number) circuit, which makes it possible to control the designated local oscillation frequency.

[0006]

EXAMPLE The operation will be described with reference to the example of FIG.
(K) is an antenna and a frequency converter installed in a remote place, and (J) is an indoor main body receiver. (J)
A part (f) surrounded by a dotted line in the figure is a control signal generator by the two-phase (multi-phase) phase modulation by the binary noise. That is, 9 is a clock generator, 10 is a phase comparator, 11 is a low-pass filter, 12 is a voltage (current) controlled oscillator, 1
Reference numeral 3 is a frequency divider, and the frequency division ratio is set by the signal input of 18, and the carrier frequency which is the output of 12 is determined. Reference numeral 14 is a binary noise generator, and the carrier wave is subjected to binary phase modulation by binary noise by 15 and output to the 19 cable lines via 16 amplifiers. Reference numeral 17 is a receiving unit for the intermediate frequency signal transmitted by the cable line.

In FIG. 1 (K), 1 is an iter body, 2 is an amplifier, 3 is a mixer, 4 is an intermediate frequency band amplifier, and (t) surrounded by a dotted line is a phase locked loop. , A phase comparator of 5, a filter of 6, and a voltage (current) controlled oscillator of 7
Simultaneously with the demodulation of the phase-modulated wave, it oscillates in phase with the specified local oscillation frequency. Reference numeral 8 is a cable for transmitting the frequency converted signal to the main unit. In this example, 18
Since the carrier frequency of the control signal that determines the local oscillation frequency can be set by inputting the specified signal of, the indoor (main body) device can select the reception frequency of the antenna unit.

In the embodiment shown in FIG. 2, a frequency control signal phase-modulated by binary noise is transmitted as an electric wave, received at the same time as a desired signal from an antenna, passed through an amplifier 2, a mixer 3, and a filter of 5. , 6 to demodulate the frequency control signal by the phase locked loop by the voltage (current) controlled oscillator and generate the designated local oscillation frequency. Reference numeral 4 is an intermediate frequency band amplifier, through which the intermediate frequency signal is transmitted through the cable line 7.

The embodiment of FIG. 3 is a phase locked loop in which the filter of 5 replaces the frequency multiplier in FIG. 2 and the input of 5 becomes the output of the intermediate frequency amplifier of 4, and the local oscillation frequency is a multiple of the intermediate frequency. Is satisfied.

According to the present invention, two-phase (multi-phase) is caused by binary noise.
Since a frequency-modulated signal that is phase-modulated is used, the reception signal is not disturbed even if it is transmitted by sharing the cable line for transmitting the reception signal, and the reception frequency can be selected remotely, so that the transmission by the cable line is possible. The signal may be an intermediate frequency whose band is limited, which improves the quality of the received signal and simplifies the main receiver. Further, it is possible to select a reception frequency by transmitting a frequency designation control signal as a radio wave to a plurality of antennas. In this case, it is possible to control a plurality of receiving devices with weak radio waves that are not restricted by the Radio Law.

[0010]

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of the present invention.

FIG. 2 is a system diagram of an antenna unit and a frequency conversion unit showing an embodiment of the present invention.

FIG. 3 is a system diagram of an antenna unit and a frequency conversion unit showing an embodiment of the present invention.

Claims (4)

[Claims] 1. A device for generating a control signal which is bi-phase (multi-phase) phase-modulated by binary noise, means for transmitting the control signal, and a device for synchronously generating a local oscillation number by the control signal. A device that performs selective reception of desired signals and frequency conversion. 2. A control signal by demodulating a two-phase (multi-phase) phase modulation by using a phase-locked oscillator as a receiving device for a two-phase (multi-phase) phase-modulated by binary noise. A frequency conversion device that generates a local oscillation frequency that is synchronized with a frequency that is 2 (even number) times the frequency. 3. The control signal receiving device according to claim 2, which also serves as an antenna, a high frequency amplifier and a mixer,
And a voltage (current) controlled oscillator.
Frequency converter. 4. A synchronous oscillator driven by a multiplier, comprising a device as an antenna, a high-frequency amplifier, a mixer, and an intermediate-frequency amplifier that doubles the output of the intermediate-frequency amplifier as the control signal receiving device according to claim 2. The frequency conversion device according to claim 2, wherein is a local oscillator.