JPH0476477A - Tracking receiver - Google Patents

Abstract

PURPOSE:To restrain phase variation between channels by generating address data from variation data of a condition by which phase error is generated between channels, and controlling a phase shifting quantity with the phase control data read out from the data. CONSTITUTION:Address data AD is made by combining optional one or over two input data through a changeover switch 17, and readout of phase control data of a memory circuit 16 is controlled by the AD. For example, when temperature measured with a sensor 18 is changed, the AD corresponding to the temperature is made by a switch 17. The phase control data readout from the circuit 16 by the AD, controls phase-shifting quantities of variable phase-shifters 5, 9, so as to set off the phase variation between a sum channel signal and difference channel signal generated by temperature variation. If signals corrected from phase shifting variation between channels are amplified with 6, 10, and phase synchronizingly wave-detected with 7, 11 to obtain detected outputs DELTAAZ, DELTAEL. Hereby phase error is automatically corrected, and a detected output signal containing no tracking error due to phase difference between channels is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a tracking receiver for automatically tracking an antenna, and more particularly to a tracking receiver in which phase fluctuations between channels are corrected.

[Conventional technology]

Conventionally, a tracking receiver has three receiving channels: an azimuth angle difference channel, an elevation angle difference channel, and a sum channel, which are circuits for receiving signals output from the tracking antenna. Then, changes in amplitude and phase of the azimuth difference channel and elevation difference channel signals are detected, each error signal is created from the difference with that of the sum channel signal, and the drive control of the tracking antenna is performed based on the error signal. It is carried out.

In general, tracking antennas may be affected somewhat due to temperature changes, etc.2
The amplitude variation between the three difference signals is not large, and the amplitude variation between the channels of the amplifier that amplifies the three signals in the tracking receiver can be made to an acceptable level for the tracking system.

On the other hand, phase changes are caused by changes in electrical length, and mechanical deformation of the tracking antenna due to changes in temperature, etc., and mechanical imbalance of the signal transmission path within the tracking receiver due to similar causes may cause differences in electrical length between the three channels. That is, a phase difference occurs. This phase difference becomes more pronounced as the signal frequency emitted by the target tracked by the tracking antenna is higher.

[Problem to be solved by the invention]

The conventional tracking receiver described above needs to be designed with care in minimizing phase fluctuations among the three reception channels that process the three received signals.

If this is a tracking receiver installed on the ground, it is not impossible to adjust the phase between the channels of the tracking receiver using the tracking antenna and collimation equipment if the surrounding environmental conditions change, but it is not easy to do so. isn't it. Furthermore, in order to communicate between satellites, it was impossible to adjust the phase between the channels of the tracking receiver mounted on the satellite.

Therefore, an object of the present invention is to obtain a tracking receiver having a plurality of reception channels with less phase fluctuation between channels.

[Means to solve the problem]

The tracking receiver of the present invention includes a frequency converter provided for each reception channel and a local oscillator that supplies a local oscillation signal to the frequency converter, and receives manual control data from a plurality of channels. or address data generation means for generating address data from sensor data that detects a change in conditions that cause an inter-channel phase error of the tracking receiver, and the phase control data in which phase control data is written in advance and that corresponds to the input of the address data. A variable phase shifter provided between a storage means from which data is read out, and a signal circuit of one or more receiving channels or the frequency converter and the local oscillator, the amount of phase shift being controlled by the readout phase control data. It has a container.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of one embodiment of the present invention.

The tracking receiver has an azimuth difference channel 1. which receives the azimuth difference signal. 2. Elevation difference channel for receiving the elevation difference signal. A sum channel 3° local oscillator 14 for receiving the sum signal. AG
C voltage detection carrier wave regeneration circuit 15, storage circuit 16. Changeover switch 17. Temperature sensor 18. It has an A/D converter 19 and a control data input port 20. The RF input signal RFΔ^2 outputted from a tracking antenna (not shown) and inputted to the azimuth difference channel l is transmitted to a frequency converter 4, a variable phase shifter 5. IF amplifier6. It is output via the synchronous detector 7 as a detection output ΔAz. Similarly, the RF input signal RFΔEL input to the elevation angle difference channel 2 is transmitted to the frequency converter 8. Variable phase shifter9. IF amplifier 10. The detection outputs ΔP and L are output via the synchronous detector 11. Also, the RF input to phase channel 3 from the tracking antenna
The input signal RFΣ is input to the frequency converter 12 and the IP amplifier 1.
3, its output is sent to the AGC voltage detection carrier wave regeneration circuit 1.
5 is input.

The local oscillation signal output from the local oscillator 14 is commonly supplied to frequency converters 4.8 and 12, and the frequency converters 4.8 and 12 convert the input RF input signal into an IF signal. The variable phase shifters 5 and 9 are phase shifters whose amount of phase shift is controlled by a digital signal, and this amount of phase shift is controlled by phase control data read out from the storage circuit 16. If the phase shifters 5 and 9 are at a position where the signal phase of the corresponding receiving channel is changed, in addition to the signal circuit through which the RF signal or IF multiplied signal passes, for example, the local oscillator 14 and the frequency converter 4 or 8 can be used. It may be placed between.

The temperature sensor 18 outputs measured temperature data as an analog signal, and one A/D converter converts this analog signal into digital data. This digital data is input to one input terminal of the changeover switch 17. Further, the control data input boat 20 is an input boat for inputting manual control data that is artificially input by a human.
It is connected to the other input terminal of the changeover switch 17.

The changeover switch 17 is used to detect not only these two digital data but also changes in other physical quantities that cause phase fluctuations between channels, such as changes in sunlight that cause distortion of the tracking antenna, etc. It is of course possible to input data from sensors. Changeover switch 17
creates address data by combining any one or more of the input data and outputs it to the storage circuit 16. The address data output from the changeover switch 17 is supplied to the address of the memory circuit 16, and controls the read data of the memory circuit 16, that is, the read of phase control data.

Here, the storage data corresponding to a predetermined address of the storage circuit 16, that is, the phase control data, is written in the ROM or RAM in advance. The phase control data corresponds to changes in physical factors that cause inter-channel phase changes, such as changes in temperature. In addition, the sum channel 3 and the difference channel azimuth channel 1 and elevation difference channel 2
The phase fluctuations occurring between the channels are canceled out.

Therefore, in this tracking receiver, for example, the temperature sensor 18
When the measured temperature changes, address data corresponding to the temperature is created by the changeover switch 17. Then, the variable phase shifters 5 and 9 are shifted so that the phase control data read out from the storage circuit 16 based on the address data cancels the change in phase between the sum channel signal and the difference channel signal caused by the temperature change. Control phase amount. The IP signal that has been corrected for phase shift variations between channels is I
The signal is input to F amplifiers 6 and 10 and amplified. The amplified difference signal channel IP signal is sent to synchronous detectors 7 and 11.
Phase synchronized detection is performed by , and the detection outputs ΔAz and Δ
EL is obtained. Here, the phase error is automatically corrected, and a good detection output signal that does not include tracking errors due to phase differences between channels can be obtained.

The AGC voltage detection carrier regeneration circuit 14 uses the level information obtained from the output signal of the sum signal channel 1 to
It creates the GC control voltage and also regenerates the carrier wave. AG
The AGC control voltage output from the C voltage detection carrier wave regeneration circuit 14 is applied to IF amplifiers 6, 10, and 13 having gain control circuits to perform gain control. As a result, the output signal level of the difference signal channel of the tracking receiver is normalized by the signal level of the sum signal level.

This is the typical operation of tracking receivers.

Further, the regenerated carrier wave is applied to the synchronous detectors 7 and 11 as a local oscillation signal for phase synchronous detection.

〔Effect of the invention〕

As explained above, the present invention reduces the inter-channel phase difference between the sum signal channel and the difference signal channel of the tracking receiver to a very small value, regardless of changes in physical factors that cause phase fluctuations between these channels. It has the effect of reducing

Furthermore, if automatic phase correction is insufficient, manual control data set by a human can also be supplied to the address of the memory circuit. As a result, it is possible to perform effective inter-channel phase correction not only due to physical change factors, but also when the inter-channel phase fluctuations of the equipment used in the receiver change over time. This is especially useful for tracking receivers mounted on satellites. It is valid.

[Brief explanation of drawings]

FIG. 1 is a block diagram of one embodiment of the present invention. 1... Azimuth angle difference channel, 2... Elevation angle difference channel, 3... Sum channel, 4, 8.12... Frequency converter, 5, 9... Variable phase shifter, 6 ,10.13・
... ■F amplifier, 7, 11... Synchronous detector, 14...
-Local oscillator, 15...AGC voltage detection carrier wave regeneration circuit, 16...memory circuit, 17...changeover switch, 1
8...Temperature sensor, 9...A/D converter, 20...Control data input board 20°

Claims (1)

[Claims] 1. In a tracking receiver that receives multiple channels and includes a frequency converter provided for each receiving channel and a local oscillator that supplies a local oscillation signal to the frequency converter, manual control data or address data generation means for generating address data from sensor data that detects a change in conditions that cause an inter-channel phase error of the tracking receiver, and the phase control data in which phase control data is written in advance and that corresponds to the input of the address data. A variable phase shifter provided between a storage means from which data is read out, and a signal circuit of one or more receiving channels or the frequency converter and the local oscillator, the amount of phase shift being controlled by the readout phase control data. A tracking receiver characterized by having a receiver. 2. The phase control data controls the variable phase shifter in a direction to eliminate an inter-channel phase difference between a sum signal receiving channel and a difference signal receiving channel of the tracking receiver. The tracking receiver described in 1.