JPH11243312A - Maximum receiving level detecting device and antenna adjusting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect a receiving signal level of high accuracy with a simple configuration even when the receiving signal level of a ground system radio terminal is a modulation signal that is not always constant in a maximum receiving level detecting device that is suitably used to detect the maximum value of a receiving signal level received by a ground system receiving terminal in a satellite communication system. SOLUTION: The receiving signal detection circuit of this device is provided with an antenna 1 capable of adjusting a receiving direction, an amplifier 2 which enables gain control that amplifies a signal received by the antenna 1, a demodulating part 3 which demodulates an output of the amplifier 2, a synchronization detecting part 4 which detects a signal synchronous state from an output of the part 3 and a maximum receiving level detecting means 5 that detects a state in which a signal level received by the antenna 1 becomes maximum by adjusting and controlling the receiving direction of the antenna 1 and the gain of the amplifier 2 and retrieving the boundary between a signal synchronous state and a signal asynchronous state by the part 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

(Contents) Technical Field to which the Invention pertains Prior Art Problems to be Solved by the Invention Means for Solving the Problems (FIG. 1) Embodiment of the Invention ・ Description of First Embodiment (FIGS. 2 to 5) , FIG. 7) • Description of a modification of the first embodiment (FIG. 8) • Description of the second embodiment (FIGS. 6, 9, and 10) • Description of a first modification of the second embodiment (FIG. 11) , FIG. 12) ・ Description of a second modification of the second embodiment (FIGS. 13 and 14) ・ Others (FIG. 15)

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a maximum reception level detection device suitable for detecting a maximum value of a reception signal level received by a terrestrial reception terminal device in a satellite communication system, and to a maximum reception level detection device. The present invention relates to an antenna adjustment method for adjusting the direction of an antenna using a level detection device.

[0003]

2. Description of the Related Art In recent years, satellite receiving systems have been widely put into practical use for broadcasting from broadcasting satellites, car navigation systems using communication satellites, and relays for weather, military, telephone lines, data lines, and the like. In such a satellite receiving system, in order to capture a weak radio wave from the satellite, the terrestrial receiving terminal device must accurately adjust the direction of the antenna toward the satellite.

When adjusting the direction of an antenna of a terrestrial receiving terminal device in a satellite communication system, it is necessary to accurately measure the level of a received signal, so that an expensive spectrum analyzer must be used. It is not easy to measure accurately with many and simple electric field strength measuring meters.

[0005]

However, in the case of a modulated wave whose spectrum distribution fluctuates over a wide frequency range, such as an FM-modulated signal spectrum, for example, even if the above-described measuring instrument is used, the maximum is accurately obtained. It is not easy to measure the reception level. In addition, for example, when receiving a satellite broadcast, when adjusting the direction of the parabolic antenna, it is necessary to know the magnitude of the reception electric field strength while looking at the reception screen. As described above, this adjustment must be performed manually while looking at the reception screen, and there is a problem that it takes time and effort.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has a simple configuration to provide a highly accurate received signal level even if the received signal level of the terrestrial radio terminal equipment is not always constant. It is an object of the present invention to provide a maximum reception level detection device capable of detecting a signal, and to provide an antenna adjustment method capable of adjusting the direction of an antenna using the maximum reception level detection device. The purpose is to:

[0007]

FIG. 1 is a block diagram showing the principle of the present invention. As shown in FIG. 1, a reception signal detection circuit according to the present invention comprises an antenna 1, an amplifier 2, a demodulation unit 3, a synchronous detection It comprises a unit 4 and a maximum reception level detecting means 5. Here, the antenna 1 is an antenna whose reception direction can be adjusted, and the amplifier 2 is an amplifier whose gain can be adjusted to amplify a signal received by the antenna 1. The demodulation unit 3 demodulates the output of the amplifier 2, and the synchronization detection unit 4 detects a signal synchronization state from the output of the demodulation unit 3.

The maximum receiving level detecting means 5 adjusts and controls the receiving direction of the antenna 1 and the gain of the amplifier 2, and the synchronous detecting section 4 searches for a boundary between a signal synchronous state and a signal asynchronous state. It detects a state in which the signal level received by the antenna 1 is maximum (claim 1). Note that the above-described reception level detecting means 5 includes the amplifier 2
With the gain of the antenna 1 adjusted to the minimum necessary gain state, the receiving direction of the antenna 1 is adjusted and controlled, and the synchronization detector 4 searches for the boundary between the signal synchronous state and the signal asynchronous state. It may be configured to detect a state where the received signal level is maximum (claim 2).

Further, the above-mentioned reception level detecting means 5 comprises:
The reception direction of the antenna 1 is adjusted and controlled while the gain of the amplifier 2 is adjusted step by step, and the synchronization detector 4 searches for the boundary between the signal synchronous state and the signal asynchronous state, so that the signal is received by the antenna 1. It is also possible to detect a state where the signal level is maximum (claim 3). Also,
By adjusting and controlling the reception direction of the antenna 1 while adjusting and controlling the gain of the amplifier 2 corresponding to each of the plurality of received signals, the synchronization detector 4 searches for the boundary between the signal synchronous state and the signal asynchronous state. The reception level detection means 5 may be configured to detect a state in which the signal level received by the antenna 1 is maximum (claim 4).

Further, the above-mentioned maximum reception level detecting means 5
And a display means for visually and audibly displaying the difference between the signal synchronous state and the signal asynchronous state in the synchronization detecting unit 4 which is detected by adjusting and controlling the receiving direction of the antenna 1 and the gain of the amplifier 2. In addition, based on the display state of the display means, the state where the signal level received by the antenna 1 is maximum is detected by searching the boundary between the signal synchronous state and the signal asynchronous state by the synchronization detecting unit 4. In addition, the reception level detecting means 5 can be configured (claim 5).

Further, according to the antenna adjustment method of the present invention, the antenna 1 capable of adjusting the receiving direction and the antenna 1
-Adjustable amplifier 2 for amplifying the signal received by the amplifier 2
And a demodulation unit 3 for demodulating the output of the amplifier 2 and a synchronization detection unit 4 for detecting a signal synchronization state from the output of the demodulation unit 3 while adjusting the gain of the amplifier 2 while receiving the signal from the antenna 1. By adjusting the direction and searching for the boundary between the signal synchronous state and the signal asynchronous state by the synchronization detecting unit 4, the signal level received by the antenna 1 is maximized, and the antenna is moved in the receiving direction in this state. It is configured to set 1 (claim 6).

[0012]

Embodiments of the present invention will be described below with reference to the drawings. (A) Description of First Embodiment of the Present Invention FIG. 2 is a block diagram showing a main part of a terrestrial receiving terminal device with an automatic antenna direction adjusting device according to the first embodiment of the present invention. The receiving terminal device 12 shown is a parabolic antenna 11, an automatic gain control type amplifier (hereinafter referred to as “AG”).
21) and a demodulation unit 23, and a phase synchronization monitoring unit 24, an error voltage display unit 26, an automatic direction adjustment control unit 29, a switching unit 22, and the like.

Here, the parabolic antenna 11 receives a signal from a satellite and has a movable mechanism for capturing an accurate direction of the satellite. That is, as shown in FIG. 5, the parabolic antenna receiving surface 11c is provided so as to be able to move up and down with respect to a support 11b rotatable with respect to the base member 11a. And a rotating shaft of an electric motor 28d is connected to a pivot portion between the parabolic antenna receiving surface 11c and the support 11b via a gear mechanism 28c.

Thus, when the electric motor 28b is operated, the column 11b is rotated, the parabolic antenna receiving surface 11c is horizontally rotated around the column 11b, and when the electric motor 28d is operated, the parabola is received. The antenna receiving surface 11c performs an elevating operation around the pivotal connection between the parabolic antenna receiving surface 11c and the support 11b, that is, rotates in the vertical direction.

The AGC amplifier 21 can variably increase or decrease the gain of the signal received by the antenna 11. The demodulation unit 23 demodulates the output of the AGC amplifier 21. For example, as shown in FIG. 3, an A / D (analog / digital) converter 23a, an equalizer 23b, a hybrid unit 23c, a mixer circuit 23d, an integration 23e, a carrier recovery unit 23f, and a clock recovery unit 23g.

Accordingly, in the demodulation unit 23 having such a configuration, the input received RF signal is converted from analog to digital by the A / D converter 23a, and the amplitude value is accurately restored by the equalizer 23b. Then, the information data (serial data) is converted into I-channel and Q-channel data by the hybrid unit 23c. Then, the I-channel and the Q-channel are multiplied by the carrier waves shifted by 90 ° in the mixer circuit 23d, and the bit is reproduced by the integrator 23e. Thereafter, a clock synchronized with the I-channel data and the Q-channel data is reproduced by the clock reproducing unit 23g, the carrier is reproduced by the carrier reproducing unit 23f, and the demodulated data is taken out.

Further, the phase synchronization monitoring section 24 monitors a frame synchronization state. For example, as shown in FIG. 4, a UW (unique word) detection section 24a and a decision circuit 2
4b, a UW pattern setting unit 24c, and a front / rear protection stage number setting unit 24d. Where UW
The detection unit 24a extracts the number of bits in the demodulated data bit string within the range of the UW length. Also, UW
The pattern setting unit 24c holds a unique word pattern, and for example, a ROM (Read Only Memory) is used as the UW pattern setting unit 24c. Further, the determination circuit 24b includes a UW detection unit 24a
Is compared with the unique word pattern from the UW pattern setting section 24c, and a match flag is output at the moment when the bit string matches the unique word pattern.

A front / rear protection stage number setting unit 24d
Is for adjusting the sensitivity of frame synchronization establishment and frame synchronization loss. That is, the reason why the phase synchronization monitoring unit 24 establishes synchronization is that the coincidence flag from the determination circuit 24b is counted m times by the forward / backward protection stage number setting unit 24d (forward protection number = m times; m is a natural number) At this time, the synchronization establishment signal is output from the front / rear protection stage number setting unit 24d. Conversely, once synchronization has been achieved, the phase synchronization monitoring unit 24 determines that the synchronization has been lost. This is because the out-of-synchronization output from the determination circuit 24b continues n times (backward protection number = n times; n is a natural number). Rear protection stage number setting unit 24d
At the time when the out-of-synchronization signal is output.

The error voltage display section 26 is for monitoring the synchronization / asynchronization at the time of reception, receives the output from the phase synchronization monitoring section 24, and displays that it is synchronous / asynchronous. Further, the automatic direction adjustment control section 29 detects the synchronous / asynchronous state of the received signal, and variably increases or decreases the gain value of the AGC amplifier 21 based on the detection result, and controls the direction of the parabolic antenna 11. For this purpose, the automatic direction adjustment type control unit 29 includes a gain control unit 25 and a rotation control unit 27, and the MPU (M
micro Processing Unit), RO
M, RAM (Random Access Memory)
y) and the like.

Here, the gain control section 25 detects the synchronous / asynchronous state of the received signal and variably increases or decreases the gain value of the AGC amplifier 21.
a, a main control section 25b, and a gain adjustment ROM 25c. The synchronization state determination means 25a monitors the output of synchronization establishment / loss of synchronization from the phase synchronization monitoring section 24. The gain adjustment ROM 25c stores the relatively high gain values in which the demodulation section 23 can operate in ascending order. It is remembered. Further, the main control unit 25b includes a synchronization state determination unit 25a.
From the output, if synchronization is established, the gain adjustment ROM 25
The pointer to the gain value stored in c is incremented, the gain value of the AGC amplifier 21 is updated to a different value, and at the same time, the rotation control unit 27 is notified of synchronization establishment.

The rotation control unit 27 receives the synchronous / asynchronous information notified from the gain control unit 25, and receives an electric motor 28d for vertical adjustment of the movable mechanism provided in the parabolic antenna 11 and a horizontal adjustment. Control such as rotation, stop, and switching of the electric motor 28b. The switching unit 22 switches the receiving mode of the receiving terminal device 12, and includes a mode for demodulating a signal received from the parabolic antenna 11 normally (mode I) and a mode for adjusting the direction of the parabolic antenna 11 (mode II). And to choose. That is, mode I is a normal reception mode, and in this mode I, the demodulation unit 23
Outputs the demodulated data to the outside, and at the same time, a part of the demodulated output is fed back to the AGC amplifier 21 as the level of the received signal received from the parabolic antenna 11. At this time, the operation of the gain control unit 25 is stopped.
On the other hand, mode II is a mode in which the direction of the parabolic antenna 11 is adjusted.
As the gain value set in the C amplifier 21, a value determined by the gain control unit 25 is used.

The operation when the direction of the parabolic antenna 11 is automatically adjusted will be described below with reference to the flowchart shown in FIG. First, the main control unit 25b sets the AG
The gain of the C amplifier 21 is set to the highest value G _N (dB) in the gain adjustment ROM 25c (step a1). That is, the counter i is set to N, and the gain satisfaction determination bit A is set to 1 at the same time. Here, when the pointer of the gain adjustment ROM 25c is incremented, the gain satisfaction determination bit A is set to A = 0 (gain too low) when synchronization is lost, and normally A = 1 (gain satisfaction). ) Has been.

Next, the main controller 25b sets both the horizontal synchronization monitoring flag H and the vertical synchronization monitoring flag V to 0 (asynchronous) (step a2), and sets the gain G
_After operating the AGC amplifier with _N (step a3),
The adjustment is performed by rotating the parabolic antenna 11 in the horizontal direction (step a4). Here, the main control unit 25b continues to monitor the output of the phase synchronization monitoring unit 24 (step a).
5) When synchronization is established, the horizontal synchronization monitoring flag H
Is set to 1 (synchronization established) (step a6), and this time, the parabolic antenna 11 is rotated in the vertical direction to perform adjustment (step a7). Again, the main control unit 25b continues to monitor the output of the phase synchronization monitoring unit 24 (step a8), and when synchronization is established, sets the vertical synchronization monitoring flag V to 1 (establish synchronization) (step a9).

If the demodulation unit 23 is operating with a gain large enough to establish synchronization, the gain satisfaction determination bit is A = 1
In this state, the main control unit 25b determines that the gain is satisfied (step a10), and decrements the counter value i (step a11). At that time, i is 1 (minimum value)
If not (step a12), the adjustment is performed again from step a2, and the gain adjustment is performed stepwise so as to lower the input level of the demodulator 23 and perform the demodulation operation.

Here, the meaning of the gain satisfaction determination bit A becoming 0 will be described. The main control unit 25b controls the gain adjustment RO
When a plurality of gain values stored in M25c are gradually reduced to a lower gain value and adjusted, the receiving state changes from a signal synchronous state to a signal asynchronous state at a certain gain value. When the signal becomes asynchronous, the gain can be adjusted at the lowest input level by returning (increase) the gain value by one and performing the adjustment again. That is, when the signal is in an asynchronous state, the satisfaction determination bit A is set to 0 (gain is too low), and otherwise, when operating with a sufficient gain value, A is set to 1 (gain satisfaction).

The flow for obtaining the lowest input level is as follows. That is, step a5, step a8
If the synchronization is not established in step, the gain of the AGC amplifier 21 is increased by one step (step a13), the gain satisfaction determination bit A is set to 0 (gain is too low) (step a14), and the process returns to step a2. When the direction is adjusted again, synchronization is established in both the horizontal and vertical directions, and the gain value at that time becomes the lowest input level. Thereafter, for the next adjustment, after returning to A = 1 (step a15),
Complete.

As described above, in this embodiment, the receiving direction of the parabolic antenna 11 and the gain of the AGC amplifier 21 are adjusted and controlled, and the phase synchronization monitoring unit 24 searches for the boundary between the signal synchronous state and the signal asynchronous state. Therefore, even if the transmission signal is a modulated wave whose spectrum distribution fluctuates every moment, the state in which the signal level received by the parabolic antenna 11 becomes maximum can be accurately determined without using an expensive spectrum analyzer. Can be detected. If the parabolic antenna 11 is fixed in this state, the parabolic antenna 11 is set in the receiving state at the maximum receiving level.

Further, the receiving direction of the parabolic antenna 11 is adjusted and controlled while adjusting the gain of the AGC amplifier 21 stepwise, and the phase synchronization monitoring unit 24 searches for the boundary between the signal synchronous state and the signal asynchronous state. Thereby, the state in which the signal level received by the parabolic antenna 11 is maximized can be detected very easily. (B) Description of Modification of First Embodiment of the Present Invention There are a plurality of satellite transmitting stations having different transmission signal levels,
If you want to select and receive these stations,
An OM table may be created for each station, and direction control may be performed using data of the station desired to be received.

That is, in this case, as shown in FIG. 8 (a block diagram showing a main part of a terrestrial receiving terminal device equipped with an automatic antenna direction adjusting device compatible with a plurality of transmitting stations), the receiving terminal device 13 In order to correspond to the transmitting station, a multi-station compatible control unit 30 is provided. Multi-station compatible control unit 3
0 indicates the synchronization state determination unit 30a, the main control unit 30b, and the RO
M selection means 30c and a gain adjustment ROM table group 30d for each transmitting station.
As a result, an appropriate ROM table corresponding to the receiving station is selected from the gain adjustment ROM table group 30d, and the pointer is returned to the main control unit 30b. Thus, in the AGC amplifier 21, an appropriate gain value is set according to each transmitting station.

Therefore, the ROM selecting means 30c has the following functions. A function of comparing the reception input level at the time of establishing synchronization with the reception input level at the time of establishing synchronization of each transmitting station, which is calculated in advance, and specifying the transmitting station that has performed direction control. The function of passing a pointer to the gain adjustment ROM table for the transmitting station that is currently being received from the gain adjustment ROM table group 30d to the main control unit 30b.

The reception level of the radio wave transmitted from each transmitting station on the satellite receiving terminal side is calculated by the line design. Therefore, even if the direction is adjusted by a station other than the desired transmitting station, the minimum level can be obtained. Since the reception levels are different, it can be determined that the station is another station. In that case, control is performed so that the direction is adjusted again for another station. In FIG. 8,
Members having the same reference numerals as those used in the above-described first embodiment have the same or similar functions, and a detailed description thereof will be omitted.

As described above, in the present modification, the first
In addition to the effect or advantage obtained in the embodiment, it is possible to selectively capture only a signal of a desired transmitting station from among a plurality of received signals. (C) Description of Second Embodiment of the Present Invention In the modification of the first embodiment described above, all the direction adjustments of the parabolic antenna are automatically controlled. May be performed manually, and the gain control may be performed semi-automatically.
Hereinafter, the semi-automatic embodiment will be described.

FIG. 9 is a block diagram showing a main part of a terrestrial receiving terminal device with a manual direction control type semi-automatic antenna direction adjusting device according to a second embodiment of the present invention. Is parabolic antenna 17, AGC
A receiving system including an amplifier 21 and a demodulation unit 23 is provided, and also includes a phase synchronization monitoring unit 24, an error voltage display unit 26, a gain control unit 25, a synchronization establishment confirmation switch 31, and a switching unit 22.

As shown in FIG. 6, the parabolic antenna 17 has a parabolic antenna receiving surface 17a with respect to a support 17d rotatable with respect to a bottom base member 17e.
It is provided so that the elevation angle can be adjusted stepwise. Further, the means for fixing the pivot portion between the parabolic antenna receiving surface 17a and the support 17d is achieved by locking the gear mechanism 17b fixed to the parabolic antenna receiving surface 17a by the fastener 17c fixed to the support 17d. It is. The fixing means between the support 17d and the base member 17e is performed by locking the gear mechanism 17f fixed to the support 17d by a fastener 17g fixed inside the base member 17e. In any of the adjustments, it is manually movable, and the adjustment position is locked each time the adjustment is made, and does not shift.

The error voltage display unit 26 outputs the output from the phase synchronization monitoring unit 24 to an LED (Light Emitt).
(ing Diode) 26a or a speaker 26b to visually and audibly notify the worker. More specifically, when the LED 26a is used, it is set to a blinking state before the synchronization is established (including the case where the synchronization is lost), and is turned on at the moment when the synchronization establishment output is received. When the speaker 26b is used, an audible low-frequency sound is emitted before synchronization is established (including the case where synchronization is lost), and the frequency of the audible sound is increased from the moment the synchronization establishment output is received. Or these LEDs 26a
And the speaker 26b may be combined.

Further, the synchronization establishment confirming switch 31 is for the operator to manually press down in response to the signal of the synchronization establishment by the LED 26a or the speaker 26b of the error voltage display section 26, and to reply to the confirmation. A reply switch 31a and a gain reset switch 31b are provided. The reply switch 31a activates the main control unit 2 of the gain control unit 25 every time the operator establishes synchronization by adjusting the antenna direction.
5b, ack (Acknowledgemen)
t). Also, the gain reset switch 31
b is manually pressed by the operator to increase the gain of the AGC amplifier 21 by one step when synchronization cannot be established even after performing direction adjustment many times.

The gain control section 25 has the following functions. A function of detecting the synchronous / asynchronous state of the received signal and variably increasing or decreasing the gain value of the AGC amplifier 21. A function for detecting that an operator has pressed down the switch 31a or the switch 31b, and the detection is provided for gain control.

In FIG. 9, the first embodiment, the first
Members having the same reference numerals as those used in the modified example of the embodiment have the same or similar functions, and thus detailed description thereof will be omitted. Hereinafter, the operation of the semi-automatic method of manually adjusting the direction of the parabolic antenna 17 will be described with reference to the flowchart shown in FIG.

First, the main controller 25b sets the gain of the AGC amplifier 21 to the highest value G _N (dB) in the gain adjustment ROM 25c. That is, the counter i is set to N, and the gain satisfaction determination bit A is set to 1 (step b1). Then set the synchronization monitoring flag V in the horizontal synchronization monitoring flag H and the vertical direction in both 0 (asynchronous) (step b2), AGC amplifier 21 by a gain value G _N
After the operation (step b3), the parabolic antenna 1
7 is manually rotated in the horizontal direction for adjustment (step b).
4). At this time, the output of the error voltage display unit 26 (LED 26
The adjustment is made while watching (or listening to) the blinking state of a or the sound of the speaker 26b. Here, when synchronization is established, the operator presses the reply switch 31a to reply to the confirmation, and the synchronization monitoring flag H in the horizontal direction is set.
Is set (step b5, step b6).

Next, adjustment is performed by manually rotating the parabolic antenna 17 in the vertical direction (step b7).
Here, the adjustment is performed while watching (or listening to) the output of the error voltage display unit 26 (the blinking state of the LED 26a or the sound of the speaker 26b). When synchronization is established, the operator presses the reply switch 31a to reply to the confirmation, and the vertical synchronization monitoring flag V is set (step b8, step b9).

Here, if the gain satisfaction determination bit A is 1 (gain satisfaction), the counter value i is decremented (step b10, step b11). If i is not 1 (minimum value) (step b12), The adjustment from step b2 is performed. The flow for obtaining the lowest input level is as follows. That is, in step b5 and step b8, when synchronization is not established despite many attempts, the gain reset switch 31b is depressed to return (increase) the gain of the AGC amplifier by one (step b1).
3) The gain satisfaction determination bit A is set to 0 (gain is too low) (step b14), and the process returns to step b2.

When the direction is adjusted again, synchronization is established in the horizontal and vertical directions, and the gain value at that time becomes the lowest input level. Thereafter, A is automatically returned to 1 for the next adjustment (step b15), and the process is completed. As described above, in the present embodiment, when the gain is adjusted stepwise, the error voltage display unit 26 is configured with the LED 26a or the speaker 26b as a means for detecting the maximum reception level, so that the worker can be synchronized. Can be known visually and audibly, and the best direction of the parabolic antenna 17 can be found. In addition, since the device is simplified by being semi-automatic, it can be used as a portable antenna adjusting jig.
Cost reduction can be achieved.

Also, the receiving direction of the parabolic antenna 17 and the gain of the AGC amplifier 21 are adjusted and controlled stepwise,
By monitoring the signal synchronization state, even if the transmitted signal is a modulated wave, it is possible to accurately measure the maximum reception level without using an expensive spectrum analyzer,
In addition, it is possible to detect a state where the signal level received by the parabolic antenna 17 is maximized. In this state, the parabolic antenna 17 is fixed in the receiving direction, and the receiving state is set at the maximum receiving level, so that the maximum receiving level and the optimum antenna direction can be obtained very easily.

(C1) Description of First Modification of Second Embodiment of the Present Invention In the above-described second embodiment, the direction of the parabolic antenna is manually adjusted and the gain control is automatically performed. Conversely, a semi-automatic method may be used in which the direction adjustment of the parabolic antenna is automatically controlled and the gain control is manually performed. For this purpose, FIG. 11 is a block diagram showing a main part of a terrestrial receiving terminal device with a semi-automatic antenna direction adjusting device of a manual gain switching type. The receiving terminal device 15 according to the present modification includes the parabolic antenna 1
1. A receiving system including an AGC amplifier 21 and a demodulating unit 23, and a device for visually and audibly displaying a synchronization state including a phase synchronization monitoring unit 24 and an error voltage display unit 26 are provided. It has a manual gain switching type control section 34 for performing manually, a switching section 22 and the like.

Further, the manual gain switching type control section 34 detects the synchronous / asynchronous state of the received signal, and the operator manually variably increases or decreases the gain value of the AGC amplifier 21 to automatically control the parabolic antenna 11. The directional control is performed. For this purpose, the manual gain switching type control unit 34
5, a rotation control unit 27, a gain volume 32 serving as an interface with an operator, and a gain confirmation button 33.

Here, the gain volume 32 is for manually switching the gain value of the AGC amplifier 21, and is specifically composed of a knob-type variable volume or the like. The gain confirmation button 33 is pressed immediately after switching the gain with the gain volume 32, and notifies the main controller 25b that the gain switching has been completed. In response, the main control unit 25b prompts the rotation control unit 27 to restart rotation of the direction adjusting motor of the parabolic antenna 11.

The gain controller 25 has the following functions. A function of detecting the synchronous / asynchronous state of the received signal and variably increasing or decreasing the gain value of the AGC amplifier 21. A function of detecting that the operator has adjusted the gain volume 32 or pressed the gain confirmation button 33, and the detection is provided for gain control.

In FIG. 11, members having the same reference numerals as those used in the first embodiment, the modification of the first embodiment, and the second embodiment have the same or similar functions. Therefore, the detailed description is omitted. Hereinafter, the operation of the semi-automatic antenna direction adjustment device of the manual gain switching type that automatically controls the direction adjustment of the parabolic antenna 11 and performs the gain control manually will be described with reference to the flowchart shown in FIG.

First, the gain volume 32 is manually set to the highest value G _N (dB), and the gain confirmation button 33 is pressed (step c1). Subsequently, both the horizontal synchronization monitoring flag H and the vertical synchronization monitoring flag V are set to 0 (asynchronous) (step c2). Next, the AGC amplifier reads the gain value (step c3), and the parabolic antenna 11 automatically starts searching for the optimal horizontal direction (step c4). The operator can know the synchronization state from the output of the error voltage display unit 26 (the blinking state of the LED 26a or the sound of the speaker 26b) (step c).
5, Step c6). After synchronization is established in the horizontal direction, the parabolic antenna 11 automatically starts searching for the optimum vertical direction (step c7, step c8). Here, when synchronization is established (step c9), the value of the selected gain volume 32 is not the minimum value (step c1).
0), the adjustment from step c2 is performed again.

The flow for obtaining the lowest input level is as follows. That is, in step c5 and step c8, if synchronization is not established despite many attempts, the gain volume 32 is returned by one (increased) (step c11), and the process returns to step c2. Then, when the direction adjustment is performed again, synchronization is established in the horizontal and vertical directions, so that the value of the gain volume 32 at that time is obtained as the lowest input level.

As described above, in this modification, when the gain is adjusted stepwise, the configuration of the error voltage display section 26 is changed to LE.
By using D26a or the speaker 26b, the operator can visually and audibly know the synchronization state, and can find the best direction of the parabolic antenna 11. Further, by using such a method, it can be used as a portable antenna adjusting jig. Furthermore, the cost can be reduced because the apparatus is simplified.

Further, the receiving direction of the parabolic antenna 11 and the gain of the AGC amplifier 21 are adjusted and controlled step by step.
By monitoring the signal synchronization state, even if the transmitted signal is a modulated wave, it is possible to accurately measure the maximum reception level without using an expensive spectrum analyzer,
The state in which the signal level received by the parabolic antenna 11 is maximum can be detected.

(C2) Description of Second Modification of Second Embodiment of the Present Invention In the above-described second embodiment and the first modification of the second embodiment, the control of the direction adjustment of the parabolic antenna and the control of the gain control are described. Although a semi-automatic method is adopted in which either one is manually performed, a completely manual method in which both control methods are manually performed may be employed. FIG. 13 is a block diagram showing a main part of a terrestrial receiving terminal device with a fully automatic antenna direction adjusting device for this purpose.
The receiving terminal device 16 shown in FIG.
Has a receiving system including a parabolic antenna 17, an AGC amplifier 21, and a demodulation unit 23, and a device for visually and audibly displaying a synchronization state including a phase synchronization monitoring unit 24 and an error voltage display unit 26. , A complete manual control unit 35 and a switching unit 22.

In the complete manual system, unlike the above-described embodiments, the complete manual control unit 35 does not refer to the synchronous / asynchronous state from the output of the phase synchronization monitoring unit 24. Instead, the operator knows the synchronous / asynchronous state of the received signal from the blinking state of the LED 26a or the sound of the speaker 26b, and manually adjusts the gain volume 32 to variably increase or decrease the gain value of the AGC amplifier 21. Let me.
The direction adjustment control of the parabolic antenna 17 is also manually performed.

The complete manual control unit 35 detects the synchronous / asynchronous state of the received signal by monitoring the input / output state of a switch or the like operated by an operator. A reply switch 31a, a gain volume 32, and a gain confirmation button 33 are provided. The gain control unit 36 detects pressing of the reply switch 31a, reading of the value of the gain volume 32, and pressing of the gain confirmation button 33, and controls the AGC amplifier 21 and the switching unit 22, and controls the main control unit 25b, Gain adjustment required ROM 25c
Is provided.

In FIG. 13, members having the same reference numerals as those used in the first embodiment, the modification of the first embodiment, the second embodiment, and the modification of the second embodiment are the same as those of the first embodiment. Since it has the same or similar function, its detailed description is omitted. Hereinafter, the operation of the completely manual antenna direction adjusting device will be described with reference to the flowchart shown in FIG.

First, the gain volume 32 is manually set to the highest value G _N (dB), and the gain confirmation button 33 is pressed (step d1). Subsequently, both the horizontal synchronization monitoring flag H and the vertical synchronization monitoring flag V are set to 0 (asynchronous) (step d2). Here, when the gain volume 32 is manually set to the gain value Gi and the gain confirmation button 33 is pressed, the AGC amplifier reads the gain value (step d3), and moves the parabolic antenna 17 horizontally to the error voltage display section. While watching (or listening to) the output of LED 26 (the blinking state of LED 26a or the sound of speaker 26b), it is manually rotated to perform adjustment (step d4, step d5). When the synchronization is established, the operator presses the reply switch 31a to reply to the confirmation (step d6).
Is adjusted in the vertical direction (step d7). When synchronization is established (step d8), the operator presses the reply switch 31a to reply to the confirmation (step d9). If the value of the selected gain volume 32 is not the minimum value (step d10), the operator re-enters. The adjustment from step d2 is performed.

The flow for obtaining the lowest input level is as follows. That is, in step d5 and step d8, if synchronization is not established despite many attempts, the gain volume 32 is returned by one (increased) (step d11), and the process returns to step d2. When the direction adjustment is performed again, synchronization is established in the horizontal and vertical directions, and the value of the gain volume 32 at that time becomes the lowest input level.

As described above, in this modification, when all the adjustments are performed manually and the gain is adjusted step by step, the operator can visually check the maximum reception level by the output of the LED 26a or the speaker 26b. It is possible to find the best direction of the parabolic antenna 17 while knowing it audibly. Further, by using such a method, it can be used as a portable antenna adjusting jig. In addition, the cost can be reduced because the apparatus is simplified.

Further, the receiving direction of the parabolic antenna 17 and the gain of the AGC amplifier 21 are adjusted and controlled step by step.
By searching the boundary between the signal synchronization state and the signal asynchronous state by the phase synchronization monitoring unit 24, even if the transmitted signal is a modulated wave, the maximum reception level can be accurately measured without using an expensive spectrum analyzer. It is possible to detect a state where the signal level received by the parabolic antenna 17 is maximum.

(D) Others The first embodiment described above, a modification of the first embodiment, a second embodiment, a first modification of the second embodiment, and a second modification of the second embodiment.
In the modification, when the direction is adjusted, the gain of the amplifier is increased or decreased stepwise to perform the adjustment. On the contrary,
With the gain value of the amplifier fixedly set to the minimum gain value at which the demodulator can operate, a method of adjusting and controlling the antenna direction to be searched in a pinpoint manner may be used.

That is, the gain of the amplifier is set in advance to a minimum value at which a signal from a satellite transmitting station desired to be received can be captured, and in that state, the receiving direction of the antenna is controlled by any one of automatic, semi-automatic, and fully manual. To adjust vertically and horizontally. And the antenna receiving surface is
Only when the satellite transmission station is correctly pointed is synchronization established and adjustment completed.

In this manner, the data stored in the gain adjustment ROM need only be the lowest gain value that can capture the signal from the satellite transmitting station that the user wants to receive, so that the used capacity is greatly reduced. In particular, when there are a large number of satellite transmitting stations having different transmission signal levels and it is desired to select and receive these stations, only a small amount of ROM is required to be mounted, and the cost can be reduced.

In the above embodiment, the parabolic antenna shown in FIG. 5 includes an electric motor for rotating the antenna receiving surface in the horizontal direction and an electric motor for rotating the antenna receiving surface in the vertical direction. Is possible in both horizontal and vertical directions. However, the parabolic antenna is not limited to this, and it may be possible to automatically adjust only the horizontal direction.

That is, as shown in FIG. 15, the parabolic antenna 18 has a parabolic antenna receiving surface 18a fixed to a support 18b rotatable with respect to a base member 18d with the elevation angle manually adjusted to the optimum direction. Further, a rotating shaft of an electric motor 28b is connected to the column 18b via a gear mechanism 18c. Thus, when the electric motor 28b is operated, the column 18b is rotated, and the parabolic antenna receiving surface 18a can be horizontally rotated around the column 18b with the elevation angle directed in the optimum direction. It is.

It is needless to say that the present invention can be variously modified and implemented without departing from the spirit of the present invention.

[0067]

As described above in detail, according to the maximum reception level detecting apparatus of the present invention, the maximum reception level detection apparatus of the terrestrial radio terminal equipment for receiving the signal from the satellite transmitting station adjusts the receiving direction. , An amplifier capable of adjusting the gain for amplifying a signal received by the antenna, a demodulation unit for demodulating the output of the amplifier, and a synchronization detection unit for detecting a signal synchronization state from the output of the demodulation unit In addition, the receiving direction of the antenna, the gain of the amplifier is adjusted and controlled, and the boundary between the signal synchronization state and the signal asynchronous state is searched by the synchronization detection unit, so that the signal level received by the antenna is reduced. By providing the maximum reception level detection means for detecting the maximum state, even if the reception signal level of the terrestrial wireless terminal device is not always constant, it is expensive. It is possible to perform highly accurate reception level detection with a simple circuit configuration without using a spectrum analyzer, etc., which has the advantage that the maximum reception level can be measured reliably, resulting in a significant reduction in antenna installation costs. There is an advantage that can be done. There is also an advantage that the direction of the antenna can be set to the receiving direction at the maximum receiving level (claim 1).

In the state where the gain of the amplifier is adjusted to the minimum necessary gain state, the reception direction of the antenna is adjusted and controlled, and the boundary between the signal synchronous state and the signal asynchronous state is searched by the synchronous detection unit. By doing so, the maximum reception level detecting means can be configured to detect a state in which the signal level received by the antenna becomes maximum, and in this case, the use of the ROM mounted on the terrestrial wireless terminal device is enabled. There is an advantage that the capacity can be greatly reduced. In particular, when there are a large number of satellite transmitting stations to be received and these stations are to be selected and received, there is an advantage that the mounted ROM can be small and the cost can be reduced (claim 2).

Further, the reception direction of the antenna is adjusted and controlled while the gain of the amplifier is adjusted step by step, and the boundary between the signal synchronous state and the signal asynchronous state is searched by the synchronization detecting section, thereby obtaining the signal. The maximum reception level detection means may be configured to detect a state in which the signal level received by the antenna is maximum. In this case, the maximum reception signal level can be measured accurately and easily. There is an advantage that the state where the received signal level becomes maximum can be easily realized (claim 3).

Then, while adjusting and controlling the gain of the amplifier corresponding to the plurality of received signals, the receiving direction of the antenna is adjusted and controlled, and the synchronization detector detects the boundary between the signal synchronous state and the signal asynchronous state. , The maximum reception level detecting means can be configured to detect a state in which the signal level received by the antenna becomes maximum. There is an advantage that it is possible to selectively capture only the signal of the desired transmitting station.

The difference between the signal synchronization state and the signal non-synchronization state is visually and audibly detected by the maximum reception level detection means by the synchronization detection section which is detected by adjusting and controlling the reception direction of the antenna and the gain of the amplifier. A signal level received by the antenna by searching for a boundary between a signal synchronous state and a signal asynchronous state by the synchronization detecting unit based on the display state of the display means. The maximum reception level detection means can be configured so as to detect the state in which the maximum is detected. In this case, since the apparatus can be semi-automatically, there is an advantage that the apparatus is simplified,
In addition, it can be used as a portable antenna adjusting jig, and has the advantage that the cost can be reduced (claim 5).

Further, according to the antenna adjustment method of the present invention, an antenna capable of adjusting a receiving direction, an amplifier capable of adjusting a gain for amplifying a signal received by the antenna, and a demodulation unit for demodulating an output of the amplifier are provided. Or, in a device provided with a synchronization detection unit for detecting a signal synchronization state from the output of the demodulation unit, the reception direction of the antenna is adjusted while adjusting the gain of the amplifier. By searching for the boundary between the state and the signal asynchronous state, the signal level received by the antenna is set to the maximum state, and the antenna is set in the reception direction where the state is obtained. There is an advantage that the direction of the antenna can be set to the receiving direction at the maximum receiving level (claim 6).

[Brief description of the drawings]

FIG. 1 is a principle block diagram of the present invention.

FIG. 2 is a block diagram showing a main part of a terrestrial receiving terminal device with an automatic antenna direction adjusting device according to the first embodiment of the present invention.

FIG. 3 is a block diagram illustrating a demodulation unit according to the first embodiment of the present invention.

FIG. 4 is a block diagram illustrating a phase synchronization monitoring unit according to the first embodiment of the present invention.

FIG. 5 is a schematic view showing a movable mechanism for automatic adjustment of a parabolic antenna applied to the present invention in the horizontal and vertical directions.

FIG. 6 is a schematic diagram showing a movable mechanism for manual adjustment of a parabolic antenna applied to the present invention in the horizontal and vertical directions.

FIG. 7 is a flowchart illustrating a control procedure of the automatic antenna direction adjusting apparatus according to the first embodiment of the present invention.

FIG. 8 is a block diagram showing a main part of a terrestrial receiving terminal device with an automatic antenna direction adjusting device according to a modification of the first embodiment of the present invention.

FIG. 9 is a block diagram showing a main part of a terrestrial receiving terminal device with a semi-automatic antenna direction adjusting device of a manual direction control type according to a second embodiment of the present invention.

FIG. 10 is a flowchart illustrating a control procedure of a manual direction control type semi-automatic antenna direction adjusting apparatus according to a second embodiment of the present invention.

FIG. 11 is a block diagram showing a main part of a terrestrial receiving terminal device with a manual gain switching type semi-automatic antenna direction adjusting device according to a first modification of the second embodiment of the present invention.

FIG. 12 is a flowchart illustrating a control procedure of a semi-automatic antenna direction adjustment device of a manual gain switching type according to a first modification of the second embodiment of the present invention.

FIG. 13 is a block diagram showing a main part of a terrestrial receiving terminal device with a completely manual antenna direction adjusting device according to a second modification of the second embodiment of the present invention.

FIG. 14 is a flowchart illustrating a control procedure of a completely manual antenna direction adjusting apparatus according to a second modification of the second embodiment of the present invention.

FIG. 15 is a schematic view showing a movable mechanism for adjusting the horizontal direction of a parabolic antenna applied to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Antenna 2 Amplifier 3 Demodulation part 4 Synchronization detection part 5 Maximum reception level detection means 11 Parabolic antenna 11a Base member 11b Support 11c Parabolic antenna reception surface 12 Terrestrial receiving terminal equipment with automatic antenna direction adjustment device 13 Multiple transmission station compatible type Terrestrial receiving terminal with automatic antenna direction adjustment device 14 Terrestrial receiving terminal device with manual direction control type semi-automatic antenna direction adjusting device 15 Terrestrial receiving terminal device with manual gain switching type semi-automatic antenna direction adjusting device 16 Complete Terrestrial receiving terminal equipment with manual antenna direction adjusting device 17 Parabolic antenna 17a Parabolic antenna receiving surface 17b Gear mechanism 17c Fastening 17d Post 17e Base member 17f Gear mechanism 17g Fastening 18 Parabolic antenna 18a Parabolic antenna receiving surface 1 b Support 18c Gear mechanism 18d Base member 21 AGC amplifier 22 Switching unit (switching unit) 23 Demodulation unit (demodulation unit) 23a A / D converter 23b Equalizer 23c Hybrid unit 23d Mixer circuit 23e Integrator 23f Carrier reproducing unit 23g Clock Reproduction unit 24 Phase synchronization monitoring unit 24a UW detection unit 24b Judgment circuit 24c UW pattern setting unit 24d Front / rear protection stage number setting unit 25 Control unit (control unit) 25a Synchronization state judgment unit 25b Main control unit 25c Gain adjustment ROM 26 Error Voltage display unit (error voltage display unit) 26a LED 26b speaker 27 Rotation control unit (rotation control unit) 28a Gear mechanism 28b Electric motor 28c Gear mechanism 28d Electric motor 29 Automatic direction adjustment type control unit (Automatic direction adjustment type control means) 30 Multi-station compatible control unit ( 30a Synchronization state determination means (synchronization state determination means) 30b Main control unit 30c ROM selection means 30d Gain adjustment ROM table group 30e Rotation control unit (rotation control means) 31 Synchronization confirmation switch 31a Reply switch 31b Gain reset switch 32 Gain volume 33 Gain confirmation button 34 Manual gain switching type control unit (manual gain switching type control unit) 35 Complete manual type control unit (complete manual type control unit) 36 Gain control unit (gain control unit)

Claims (6)

[Claims] An antenna capable of adjusting a receiving direction, an amplifier capable of adjusting a gain for amplifying a signal received by the antenna, a demodulator for demodulating an output of the amplifier, and a demodulator for demodulating an output of the amplifier. A synchronization detection unit that detects a signal synchronization state, and a reception direction of the antenna, and a gain of the amplifier are adjusted and controlled, and the synchronization detection unit searches for a boundary between a signal synchronization state and a signal asynchronous state, thereby obtaining the antenna. A maximum reception level detecting means for detecting a state in which the signal level received at the maximum is detected. 2. The apparatus according to claim 1, wherein said maximum reception level detection means adjusts and controls a reception direction of said antenna while adjusting a gain of said amplifier to a minimum necessary gain state. 2. The maximum reception level detection device according to claim 1, wherein the maximum reception level detection device is configured to detect a state in which a signal level received by the antenna is maximum by searching for a boundary with a signal asynchronous state. 3. The maximum reception level detection means adjusts and controls the reception direction of the antenna while adjusting the gain of the amplifier in a stepwise manner, so that the synchronization detection unit switches between a signal synchronous state and a signal asynchronous state. 2. The maximum reception level detecting device according to claim 1, wherein a state in which a signal level received by said antenna is maximum is detected by searching for a boundary. 4. The maximum reception level detection means adjusts and controls the gain of the amplifier corresponding to a plurality of reception signals, and adjusts and controls the reception direction of the antenna. 2. The maximum reception level detection according to claim 1, wherein a state in which a signal level received by the antenna is maximum is detected by searching for a boundary between the state and the signal asynchronous state. apparatus. 5. The synchronization detection section, wherein the maximum reception level detection means detects a difference between a signal synchronous state and a signal asynchronous state by adjusting and controlling a receiving direction of the antenna and a gain of an amplifier. A display means for audibly displaying, and wherein the maximum reception level detecting means searches for a boundary between a signal synchronous state and a signal asynchronous state in the synchronous detecting section based on a display state on the display means. 2. The maximum reception level detection device according to claim 1, wherein the maximum reception level detection device is configured to detect a state in which a signal level received by the antenna is maximum. 6. An antenna capable of adjusting a receiving direction, an amplifier capable of adjusting a gain for amplifying a signal received by the antenna, a demodulator for demodulating an output of the amplifier, and a demodulator for demodulating an output of the amplifier. In a device provided with a synchronization detection unit for detecting a signal synchronization state, the reception direction of the antenna is adjusted while adjusting the gain of the amplifier, and the boundary between the signal synchronization state and the signal asynchronous state is adjusted by the synchronization detection unit. , The signal level received by the antenna is maximized, and the antenna is set in a receiving direction in which this state is reached.