CN2572670Y

CN2572670Y - Frequency mixingantenna amplifier

Info

Publication number: CN2572670Y
Application number: CN 02275470
Authority: CN
Inventors: 段保国
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-09-28
Filing date: 2002-09-28
Publication date: 2003-09-10
Anticipated expiration: 2012-09-28

Abstract

The utility model discloses a frequency mixing antenna amplifier, which is formed by the sequential connection of a filter 1, a mixer 1, a filter 2 and a mixer 2, wherein, the wire connecting terminal of an antenna is connected with the input terminal of the filter 1, the output terminal of the filter 1 is connected with the input terminal of the mixer 1, the output terminal of the mixer 1 is connected with the input terminal of the filter 2, the output terminal of the filter 2 is connected with the input terminal of the mixer 2, and the output terminal of the mixer 2 is connected with a radio receiver. The utility model has a relatively narrow passing band, which can reduce interference signals entering the receiver and enhance the sensitivity of the radio receiver. The utility model can enhance the capability of the radio receiver to resist image frequency interference.

Description

The mixing type antenna amplifier antennafire

(1) technical field

The utility model belongs to the radio communication technology field, is specifically related to the antenna amplifier antennafire that a kind of radio receiver uses.

(2) background technology

Common antenna amplifier antennafire is made of triode or field effect transistor and their combinational circuit, input, output difference L in parallel, C resonant tank at triode, make triode be in the linear amplification state, utilize L, C resonant tank to select the frequency of the received signal of wanting.The shortcoming of these antenna amplifier is: the passband broad, suppress not strong to interference signal.

(3) summary of the invention

The purpose of this utility model provide a kind of passband narrower, can reduce the interference signal that enters receiver; The mixing type antenna amplifier antennafire strong to the image frequency interference rejection capability.

The technical solution adopted in the utility model is: the mixing type antenna amplifier antennafire is to be connected in turn by filter 1, frequency mixer 1, filter 2, frequency mixer 2 to constitute, the input of the wiring termination filter 1 of antenna, the input of the output termination frequency mixer 1 of filter 1, the input of the output termination filter 2 of frequency mixer 1, the input of the output termination frequency mixer 2 of filter 2, the output termination radio receiver of frequency mixer 2.

Radio signal earlier by filter 1 in frequency mixer 1 with the local oscillation signal mixing, mixing produce with frequently and difference frequency component by

filter

2,2 permissions of filter and frequently or difference frequency one of them pass through.With the signal of filter 2 output in frequency mixer 2 with the local oscillation signal mixing.Produce after the mixing with frequently and difference frequency component, they one of them must be identical with the Radio Signal Frequency of input, also must keep modulation system and information constant.Compete to look the cost of realizing antenna amplifier antennafire and condition with frequency component or difference frequency component and determine as for studying carefully, cannot treat different things as the same.The utility model output with frequently and difference frequency component, one of them differs from two local frequencies for our institute's unwanted signal, this signal and the signal that we will receive on frequency.So this signal of the radio receiver that connects behind amplifier filtering easily can not impact receiver.Because the utility model has utilized frequency mixer as amplifying device, this just exists third order intermodulation interference, third order intermodulation to disturb.The inhibition that third order intermodulation interference, third order intermodulation are disturbed is to make frequency mixer be in linear working state.Because of there not being amplifier element before the frequency mixer, so can make frequency mixer on a large scale, keep linear.Frequency mixer can use both-end balanced mixing device, keeps it to work in the linear amplification state, and this also just makes noise be inhibited.

Advantage of the present utility model:

A, the sensitivity that has improved radio receiver.Owing to utilized the principle of frequency mixer to select the signal frequency that will receive, so the frequency bandwidth of filter 2 can be done very narrowly.Frequency bandwidth of the present utility model is much narrower than common antenna amplifier antennafire, so can improve the sensitivity of radio receiver.

B, can improve the anti-image frequency interference capability of radio receiver.As everyone knows, when local frequency was higher than the signal frequency that will receive, image frequency was than the high twice IF-FRE of receive frequency; If the oscillator frequency of oscillation be lower than when wanting the received signal frequency, then image frequency is than the low twice IF-FRE of received signal frequency.Inhibition to image frequency is disturbed is realized by filter before the frequency mixer 11 and the higher intermediate frequency of selection.

(4) description of drawings

Fig. 1 is the circuit theory diagrams of common antenna amplifier antennafire;

Fig. 2 is a structural representation of the present utility model;

Fig. 3 is the circuit theory diagrams of the utility model execution mode;

(5) embodiment

The signal input part of antenna connects the middle all coil T1 primary sides in the filter 1 in the execution mode, the elementary other end ground connection of T1, T1 time level connects the ∏ mode filter of being made up of capacitor C 1, C2, C3, all coil T2's is elementary in the output termination of this filter, T2 level connects 1,2 pin of integrated circuit (IC) 1,2 foot meridian capacitor C4 ground connection; The 3 pin ground connection of IC1,7 foot meridian capacitor C6 ground connection, 6 pin, 7 pin cross-over connection capacitor C, 5,6 pin connect capacitor C 8, another termination inductance coil T3 of C8 and capacitor C 9, C10, another termination coaxial capacitance of C10 C11a, T3, C9 and Clla other end ground connection; 8 pin of IC1 connect 3 pin of regulator block IC3, the 2 pin ground connection of IC3, and 1 pin meets dc power anode Vcc; All coil T4's was elementary during 4,5 pin of IC1 connect, T4 time level connects the T mode filter of being made up of crystal JT1, JT2 and capacitor C 12, all coil T5's is elementary in the output termination of filter, T5 level connects 1,2 pin of integrated circuit (IC) 2, the element that 3,6,7 pin of IC2 connect is identical with IC1,8 pin connect 3 pin of IC3, and 4,5 pin of IC3 connect radio receiver; 3 foot meridian capacitor C7, the C13 of IC3, C19 ground connection, its 1 foot meridian capacitor C20, C21 ground connection.

Element of the present utility model is selected:

frequency mixer

1 and 2 can and have the integrated circuit of mixing function such as NE602, MC1596 wait and constitute with triode, field effect transistor and their combinational circuit.The simple LC serial or parallel connection of filter 1 usefulness loop can meet the demands, and the both available LC band pass filter of filter 2 also can use other filter.

During installation, antenna amplifier antennafire can be installed in the antenna box independently, and antenna box and antenna are installed together.Also antenna amplifier antennafire can be installed in radio receiver inside.

Consider with the angle that is connected, controls of receiver from antenna amplifier antennafire, local oscillation circuit uses variable capacitance diode, tuning voltage on the variable capacitance diode is controlled by radio receiver, also can be connected between voltage source and the variable capacitance diode with a variable resistor, resistance by manual controlling resistance changes the tuning voltage on the diode, thereby controls receive frequency of the present utility model.Perhaps replace variable capacitance diode with the duplex variable capacitance.

Claims

1, a kind of mixing type antenna amplifier antennafire, it is characterized in that it is connected in turn by filter 1, frequency mixer 1, filter 2, frequency mixer 2 constitutes, the input of the wiring termination filter 1 of antenna, the input of the output termination frequency mixer 1 of filter 1, the input of the output termination filter 2 of frequency mixer 1, the input of the output termination frequency mixer 2 of filter 2, the output termination radio receiver of frequency mixer 2.

2, mixing type antenna amplifier antennafire according to claim 1, the signal input part that it is characterized in that antenna connects the middle all coil T1 primary sides in the filter 1, the elementary other end ground connection of T1, T1 time level connects the ∏ mode filter of being made up of capacitor C 1, C2, C3, all coil T2's is elementary in the output termination of this filter, T2 level connects 1,2 pin of integrated circuit (IC) 1,2 foot meridian capacitor C4 ground connection; The 3 pin ground connection of IC1,7 foot meridian capacitor C6 ground connection, 6 pin, 7 pin cross-over connection capacitor C, 5,6 pin connect capacitor C 8, another termination inductance coil T3 of C8 and capacitor C 9, C10, another termination coaxial capacitance of C10 C11a, T3, C9 and C11a other end ground connection; 8 pin of IC1 connect 3 pin of regulator block IC3, the 2 pin ground connection of IC3, and 1 pin meets dc power anode Vcc; All coil T4's was elementary during 4,5 pin of IC1 connect, T4 time level connects the T mode filter of being made up of crystal JT1, JT2 and capacitor C 12, all coil T5's is elementary in the output termination of filter, T5 level connects 1,2 pin of integrated circuit (IC) 2, the element that 3,6,7 pin of IC2 connect is identical with IC1,8 pin connect 3 pin of IC3, and 4,5 pin of IC3 connect radio receiver.