JPH01136427A - Satellite broadcast receiver - Google Patents

Abstract

PURPOSE:To simply receiver a BS broadcast by frequency-converting a broadcast signal into a UHF broadcast wave signal of other channel so as not to give a fault to a BS-IF signal converted into the frequency of the UHF broadcast wave band. CONSTITUTION:An intermediate frequency is set between a VHF channel and a UHF channel and most of the 1st and 2nd local oscillating frequencies f1, f2 is selected at the outside of the television channel band. When the input channel of the UHF broadcast signal subject to channel conversion and the output channel to convert it are decided, a microprocessor gives a data commanding the local oscillating frequency in response to the input/output channel according to the program of a ROM memory to the 1st and 2nd local oscillators LOSC 1, 2 and the data commanding the pass band of the 1st and 2nd bandpass filters BPFs 1, 2 to the 1st and 2nd D-A converters DA 1, 2 respectively. Thus, the local oscillating frequencies f1, f2 and the pass band are locked.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a satellite broadcast receiving device, and particularly to a UHF and VH
The present invention relates to a simple device that can be added to a television broadcast receiving system to easily receive satellite broadcasts.

[Summary of the Invention] A simple device that can receive satellite broadcasts by inserting it into the middle of the signal transmission coaxial cable of an existing VHF and UHF television broadcast receiving system, which is converted to a frequency in the UHF band. The BS-IF multiplied signal, a received UHF signal frequency-converted to a UHF signal of another channel so as not to interfere with this signal, and a received VHF signal are mixed and output.

[Conventional technology] Up until now, television broadcasting has been based on VHF (76-2
22 MHz) and UHF (470 to 770 MHz) broadcast waves were received either individually or collectively at communal reception facilities in apartment complexes. In this collective reception system, only VHF broadcasts are transmitted, or in areas where VHF and UHF broadcast waves can be received, UHF broadcast waves are frequency-converted to vacant channels in the VHF band and transmitted, or VHF and UHF broadcast waves are transmitted as they are. It is transmitting U/V.

To receive satellite broadcasts using such existing systems, the BS-UHF (FM) transmission method is adopted, in which the signal from the BS (satellite) receiving antenna is multiplied by BS-IF times the frequency that can be transmitted in the UHF band. Signal 1035-1335
MHz).

Furthermore, the BS down converter converts the signal to a UHF band frequency and transmits it to the U/V transmission line, and the BS up converter converts the signal frequency to BS-IF times again at each terminal and supplies it to the BS tuner to receive satellite broadcasting. was.

In this case, when the existing UHF broadcast reception signal interferes with the frequency-converted BS reception signal, the U/
A U converter converts the above UHF broadcast reception signal to another UH signal.
A method is used in which the frequency is converted to the F channel to enable transmission of the BS reception signal.

[Problems to be Solved by the Invention] However, since the UHF broadcast wave bands received in each region are different, the converters must be manufactured according to the channels designated by each region. Since the manufacturing of the product must be made to order with different specifications depending on the region, it is not possible to have an immediate delivery system, which causes production and management problems such as long delivery times, and also has the disadvantage that it cannot be used outside the specified region.

Therefore, the purpose of the present invention is to
- UHF can be manufactured regardless of channel specifications and can be manufactured using existing UHF.

To provide a simple device that can receive BS broadcast waves by simply adding it to a VHF television receiving system.

[Means for Solving the Problems] The present invention relates to a satellite broadcast receiving device made to achieve the above object, and includes a VHF and/or UHF signal input terminal, and a BS that has been converted to a frequency in the UHF broadcast wave band. −
An IF double signal input terminal, a converter that converts the frequency of UHF broadcast waves from the input terminal into UHF broadcast waves of other channels, and mixes the VHF signal, the VHF signal from the converter, and the BS-IF double signal from the input terminal. and a mixing circuit section that outputs the signal.

[Operation] The UHF signal received by the universal converter is converted to the frequency of the UHF broadcast wave band by the BS-IF.
UHF of other channels to avoid double signal interference
Since the frequency is converted to broadcast wave signals, these signals and VH
The F signal can be mixed with the F signal and transmitted to the subsequent television system via a single coaxial cable.

[Examples] The present invention will be described below with reference to examples shown in the drawings.
FIG. 1 shows an embodiment of a satellite broadcast receiving apparatus according to the present invention.

In the same figure, A is an input terminal for a VHF signal or a VHF/UHF mixed signal, B is an input terminal for a UHF broadcast wave, and C is an input terminal for a UHF broadcast wave.
BS-IF multiplied signal input terminal converted to the frequency of the HF broadcast wave band; D is the output terminal.

E is a branching circuit that splits the above mixed signal into a VHF signal and a UHF broadcast wave signal.JSW is an input signal selection switch, and UC
is a universal converter, F is B from the above input terminal
UH from S-IF double signal universal converter UC
G is a mixing circuit unit that mixes the VHF signal and the mixed signal from the mixing circuit unit F, and G is a mixing amplification unit that mixes the VHF signal and the mixed signal from the mixing circuit unit F and outputs the mixed signal to an output terminal.

The above device AR is, for example, an existing UHF/V as shown in Figure 2.
Added to HF television receiving system.

In Figure 2, AP is an existing UHF/VHF television receiving system, ANT is a VHF broadcast wave receiving antenna,
ANT is a UHF broadcast wave receiving antenna, M is a UHF signal and VHF signal mixer, AMP is a line booster, CA
is a coaxial cable that transmits the mixed signal from the mixer M to the television receiver side.

In order to receive satellite broadcasting with the above system AP, the machine mAR shown in FIG. The input terminal C is connected to the output of the down converter DW of the system AP on the BS side.

A, NT is a BS broadcast wave receiving antenna, BSC is a BS converter, and the BS signal from antenna ANT is
The signal is converted into an S-IF signal, and further frequency-converted into a signal in a predetermined VHF broadcast wave band by a down converter DW.

In this case, nothing is connected to the input terminal B and the input signal changeover switch SW is connected to the branching circuit E, but the UH
When the F broadcast wave signal and the VHF signal are not mixed, a coaxial cable on the UHF receiving antenna side is connected to terminal B.

In addition, when using this device, the BS on the TV receiver side
It is assumed that an up-converter is used to convert the mixed signal from the output terminal to the BS-IF multiplied signal frequency of the down-converted BS-IF multiplied signal source.

FIG. 3 shows an example of the universal converter. In Figure 3, IN is an input terminal, OUT is an output terminal, and B
PFI and BPF2 are the first and second voltage variable band pass filters, respectively, MIXI and MIX2 are the first and second mixers, respectively, AMPi, AMP2 and AMP3 are the first and second voltage variable band pass filters, respectively. The second and third amplifiers, IF BPF are intermediate frequency band pass filters, DAI and DA2 are the first and second DA converters, respectively, LO3CI and LO8C2.
are the first and second voltage variable local oscillators of the PLL system, CPU is the microprocessor, CH is the channel set digital switch, ROM is the ROM memory, L
AM is an indicator lamp.

As shown in the figure, the first voltage variable band pass filter BPF
1. The first amplifier AMPI, the first mixer MIX1. Intermediate frequency band pass filter IFBPF, second amplifier A
MP2, second mixer MIX2, second voltage variable bandpass filter BPF'2, and third amplifier AMP3 are connected in series between input/output terminals IN and OUT, respectively, in this order.

Then, the first and second voltage variable bandpass filters B
PFI and BPF2 are coupled to the microprocessor CPU via first and second DA converters DAI and DA2, and first and second local oscillators LO8CI and LO3C2 are coupled to the microprocessor CPU;
Each local oscillation frequency f1. The output of f2 is the first and second
Mixer MIX1. Supplied to MIX2.

Furthermore, the universal converter of FIG. 3 sets its intermediate frequency between the VHF channel and the UHF channel, and also sets the first and second local oscillation frequencies f, , f,
Most of the channels are selected to be outside the TV channel band (parts within the band are all set to the UHF channel band edge). Further, the ROM memory stores in advance a program etc. that instructs control steps for each circuit necessary for frequency channel conversion.

Now, once the input channel of the UHF broadcast wave signal to be converted and the output channel to be converted are determined, the input/output channel data is read into the microprocessor CPU by setting the digital switch CH. According to the program in the memory, data instructing the local oscillation frequency according to the input channel is sent to the first local oscillator LO5CI, and data instructing the passband of the first bandpass filter BPFI is sent to the first DA converter DA1. and data instructing the local oscillation frequency according to the output channel to the second local oscillator LO8C2, and data instructing the pass band of the second band pass filter BPF2 to the second DA converter DA2. give. As a result, the local oscillators LO8CI, LO8C2, D-
In the A converters DAI and DA2, respective control voltages are determined based on the above data, and the local oscillation frequencies f1. f, and the passband are locked. Fourth
The figure is a flowchart showing the control operation of the microprocessor CPU.

[Effects of the Invention] As is clear from the above explanation, according to the present invention, BS broadcasting can be easily received by simply adding it to an existing UHF or VHF television receiving system without making any major changes to the system. Moreover, since there is no need to manufacture equipment with different specifications for each region, it is highly mass-producible and has great practical effects.

[Brief explanation of the drawing]

1 and 2 are block diagrams showing one embodiment of the present invention, FIG. 3 is a block diagram illustrating a universal converter used in the above embodiment, and FIG. 4 is a flowchart for explaining its operation. It is. A, B, C... Input terminal, D...
...output terminal. E・・・・・・・・・Branching circuit, SW・・・・・・
・Input signal selector switch, UC・・・・・・Universal converter, F・・・・・・Mixing circuit,
G......Mixing amplification section. Patent applicant Nippon Antenna Co., Ltd. Agent Patent attorney Eiji 1) Takeshi Part 3 Figure F

Claims (1)

[Claims] A VHF and/or UHF signal input terminal, an input terminal for a BS-IF signal converted to a UHF band frequency, a universal converter that converts the frequency of UHF broadcast waves from the input terminal to UHF broadcast waves of other channels, and a VHF A satellite broadcast receiving device comprising: a mixing circuit unit that mixes and outputs a signal, a VHF broadcast wave from the converter, and a BS-IF signal from an input terminal.