JPS6294026A - Transmission electric power control system - Google Patents

Abstract

PURPOSE:To continue a transmission electric power control without intermission even when the changeover of a transmission system takes place by stopping the level control to raise an alarm when the detected voltage of a level detection means reaches the outside of a limit with respect to a collation voltage. CONSTITUTION:A detection voltage VD detected by a level detector DET5 is compared with a collation voltage VR by a level controller CONT6 to control the control signal 101 of an active transmission system 1 during transmission thereby obtaining the state of VD=VR through the coincidence of the both. Whether or not the voltage VD is within the 1st limit + or -alphadB with respect to the voltage VR is discriminated, and when the voltage VD is within the alphadB, the control signal 101 of a pin diode attenuator is controlled to keep the normal control operation. When the limit value is exceed and the voltage VD is larger than the voltage VR, the control signal is not revised but an alarm is raised. When the voltage VD is smaller conversely, the voltage VD is compared again with a reference voltage VC, and when the difference between the voltage VD and VC is within the 2nd limit + or -betadB, the normal control is applied.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a transmission power control system, particularly for frequencies above the sub-millimeter wave band where rainfall attenuation is large. At the Earth station in use,
Ability to compensate for uplink rain attenuation? The present invention relates to a transmission power control method.

[Conventional technology]

Frequencies above the quasi-millimeter wave band (11-14 GHz band) where rainfall attenuation is large? In an earth station using a satellite communication method, it is necessary to control the fluctuation noise of the earth radiated power (EIRP) within a certain range (for example, ±0.5 dB), or to control the earth station's transmission power when the rainfall attenuation is large. Increase uplink rain attenuation? Transmission power control is required to compensate. Various methods have been proposed for this transmission power control, but downlink rain attenuation compensation is measured using, for example, beacon radio waves transmitted from satellites, and from this measured value, it is possible to determine the amount of amplifier link attenuation. The estimation control method that estimates and increases the chipping during transmission by that amount is a method that is often used as a relatively simple and highly practical method. In closed-loop control, the detection voltage of the level detector is compared with the reference reference voltage, and all level control circuits such as variable attenuators installed in the transmission system are controlled so that the two match. This can be easily realized by setting the sum of the reference voltage for controlling EIRP i to be constant during all clear weather and the correction voltage for increasing the total EIRP during rainy days = 9. Is there redundancy in the transmission system at the earth station? In many cases, the transmission system of the backup system has a two-line configuration, one for active use and one for backup, but in this case, the backup transmission system does not have closed loop control, and the level control circuit of the backup system has a constant level control circuit. Add a control signal (when each component of the standby system is in the royal state, EI1%P is the set value for clear weather), and when the output of the working system decreases and the switch is made to the standby system. Will EiRP become excessive and interfere with communication between other earth stations? It is designed to prevent all damage. In addition, in order to completely prevent the transmission of excessive ELRP i due to failure of the control system, the detection voltage of the level detector and the reference voltage are set to a predetermined value (for example, ±3 dB).
If there are any discrepancies above, will it be immediately controlled? Canceled and alert? is configured to occur.

[Points to be solved by the invention]

However, in the conventional configuration described above, if an abnormality occurs in the current transmission system during rain and the system is switched to the backup system, if the correction voltage due to rain attenuation is large and exceeds the equivalent of 3 dB, A constant control signal is applied to the level control circuit of the standby system, and when it switches to the standby system, the EIRP id becomes the EIRP on a clear day, and the EIRP of the working system, which had been boosted to compensate for rain attenuation. Since the voltage decreases by 3 dB or more, there is a difference of 3 dB or more in VC between the detection voltage of the level detector and the reference voltage, resulting in a disadvantage that transmission power control is stopped and n2 reward is generated. The purpose of the present invention is to provide a transmission power control method that eliminates these drawbacks and can also handle switching during rain attenuation without completely losing other conventional functions. It is to provide.

[Means for solving problems]

The transmission power control method of the present invention is a level control circuit in which the output level is controlled by modifying the control signal. In preparation for that, a transmission means that switches the power of one of the 92 transmission systems and transmits power, and the equal power transmitted by this transmission means? What level detection means to detect and the detection pressure of this level detection means? A level control means for controlling the entire level control circuit of the transmitting system during transmission so that the two match by comparing with a reference voltage, a rain attenuation measuring means for emitting a complete reduction of radio waves due to rain, and a rain attenuation measuring means. From the output of the means and the reference voltage set during transmission during clear weather, the rain attenuation measuring means which generates the reference voltage and k E is obtained from the earth station sender 'i=, in the force control formula, the level ail! The control means is predetermined with respect to the reference voltage 1〆L when the detected voltage of the bell detection means indicated by 1 is: n, 7'Il: when VC is within the first limit value and when the detected voltage is within the first limit value. The reference voltage = the first
When the voltage drops beyond a limit value (7), but is within a second limit value predetermined with respect to the reference voltage, the level control circuit is fully controlled.

If the detected voltage does not meet the above conditions, all control of the level control circuit is stopped and an alarm is issued? There are nine configured to occur.

〔Example〕

Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows the system configuration of an embodiment of the present invention (!"incorrect block + g. The transmission system shown in FIG. In Figure 1, the output of the active transmitting system 1) is divided into a redundant transmitting system in which the output is switched by a switch (SW) 3 and transmitted, and a part of the transmitting output is sent via a directional coupler (DC) 42 to l/Detector (DE
The rt detection voltage VD detected by T) 5 is compared with the reference voltage VB by a k level control device (CONT) 6,
It is configured to control the active transmission system 10 control signal 101 that is being transmitted until the two match and VD=vIL. Is the verification voltage ■R the transmission power? Standard E for clear skies
Rain attenuation compensation obtained from the reference voltage V○ for controlling to I⇠P and the carrier-to-noise power ratio (C/N) of the beacon signal detected by the beacon receiver (REC) 7 for rain attenuation measurement. It is given as the sum of the correction voltage vU for EIR
The system is configured to prevent Pg movement and increase the transmission power of the amplifier link during rain in the same control loop. The active transmission system 1 and the backup transmission system 2 are equipped with an n up converter (U/C) 11 and a 21° bin diode attenuator (P
IN) 12 and 22° Power amplifier (FA) 13 and 23
The level control circuit PIN121CU of the active transmission system 1 that is transmitting, when Vp(V), decrease the attenuation amount and increase the chip during transmission h. When VD>VB, increase the attenuation amount and increase the transmission power. Control signal 10 to reduce
1 is added, and as a result, control is performed such that VD=V at all times. Ru. At this time, the control signal 102 of the backup transmission system 2 always has a constant value regardless of the VD (EI when all the components of the transmission system are in a normal state).
The circuit is configured such that a voltage such that RP is the set value in clear weather is supplied. 1. Receive the beacon signal sound that is always transmitted from EC7j4 at a constant EIRP and detect its C/N2. A/D summer replacement and C0NT6
Send to. A level control unit sends a control signal 101 so that the C0NT6 fall detection voltage VD and reference voltage vR match, and the uplink rain attenuation is determined from the C/N information of REC7. It consists of a rain attenuation correction section which calculates a correction voltage VUk for compensation and adds it to the reference voltage c to generate a reference voltage VRk. The rain attenuation of the amplifier link can be estimated by dividing the rain attenuation of the downlink (the rain attenuation is inversely proportional to the square of the frequency), and the rain attenuation of the downlink can be calculated by dividing the rain attenuation of the downlink. Since it can be easily calculated from the deterioration from the C/N during clear weather, the uplink correction voltage Vuk can be obtained from the received C/N. C0NT6 is a microprocessor (CPU)
It is configured to include a correction voltage Vty k for uplink rain attenuation from the C/N output of R・EC7,
For example, ROM? This is the EIRP for all clear skies.
2 Add to the reference voltage VC to be set and check the reference voltage■
3 Complete calculation 1-1 Compare this vR and VD and calculate the control signal 1
01? is configured to occur.

FIG. 2 is a flowchart of the operation performed by the level control section of C0NT6 in the first garden, and the control operation of FIG. 1 will be explained in more detail below with reference to the flowchart shown in C.

First, in step 201VC, DET5 detects the detection voltage V
When all D (in dB display) are detected, in step 202, the predetermined first
Is it within αdB (eg ±3dB) above the limit value? If it is within αdB (3dB), step 20
Bin diode attenuator control signal 1 according to 3-207
Normal control operation by controlling 01? Continue, but at the limit α
If it exceeds dB (3 dB)2, it is determined in step 208 whether VD is larger or smaller than ■a, and if it is larger, the process moves to step 210' (step 7 does not update the control signal 4).
F-reporting occurs. Conversely, if VD is small, step 20
Moving on to 9, compare again with the reference voltage Vc (dB display)? As a result, the difference between VD and
If the difference is within β dB (for example, ±3 dB) above the limit value, the system goes to steps 203-207 and performs all normal control, and when the difference exceeds β dB (3 dB), the control is stopped and an alarm is issued. has been done. This configuration [J:f
If the rain attenuation of the uplink exceeds 3 dB, if switching to the standby transmission system is performed during rain, the VD and vR attenuation will be lower by more than 3 dB at the time of the switch, but step 209 If there is no abnormality in the backup transmission system and control system, the control is continued as is, and the transmission power of the backup transmission system is increased until VD=V. Operation with compensation? It is possible to continue. In contrast, in the conventional method, steps 208,
If there is no 209 and the difference between VD and ■ is large in step 202, control immediately? Stop and alarm? Since it is configured so that the changeover occurs when the rain attenuation is large, the control will be stopped with +fff Tentoki Inusamurai RP and the A-to' alert will not be issued. Transmission EI
There was a drawback of line failure due to lack of RP.

Step 202 is provided to prevent the control system from performing the desired control operation when there is a sudden change in the transmitted power due to a control loop failure or input signal disconnection. It has also been applied to the control system of a conventional microwave band radio station, which is intended only to prevent fluctuations in transmission power without compensation.

In order to perform uplink rain attenuation compensation all at the same time in this control system, simply collate C0NT6 'f':i
It is not sufficient to simply set the voltage VRk as the sum of the reference voltage vc and the correction voltage vU, and this results in the drawback that the control is interrupted when switching between the working and standby modes occurs during rain. On the other hand, in the tQ formation of Honda's example,
h"Inu Samurai's %I] All of the above-mentioned drawbacks in switching during rain can be eliminated without impairing the protective operation against abnormalities such as failure of the control loop or interruption of the input signal.

In the embodiment shown in FIG.
Bin diode attenuator as an i-controlled level control circuit? Are you using a bin diode attenuator but other methods such as a variable gain amplifier? It can be used, and its insertion position may be at the front stage of the intermediate frequency converter rather than after the up-converter. Also, in the explanation of Fig. 2, each voltage (VD, vc, Vu) is also expressed as a numerical value expressed in dB.
Although it is assumed that digital processing can be performed by the UCPU in C0NT6, the present invention is not limited to this.

Furthermore, both the first limit value α and the second limit value β are ±3 dB.
However, α and β do not necessarily have to be the same, nor do the limit values on the positive (+) side and the negative (-) side necessarily have to be the same. For example, +α1°-C2( α1≠
Even if you set it to α2), it will be ↓.

〔Effect of the invention〕

If the IC described in detail above and the transmission power control method of the present invention have a conventional protection function against abnormal situations such as input signal disconnection or control loop failure? Even if the transmission system is switched during a rain event when the rain attenuation exceeds the first limit value, the transmission power control can be continued without interruption without any damage, and the reliability of the line is improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the system configuration of an embodiment of the present invention, and FIG. 2 is a flowchart of the control operation of FIG. 1. 1... Working transmission system, 2... Preliminary transmission system,
3...Switcher (SW), 4...Directional coupler (L)C), 5...Level detector (DET)
), 6...control device (CONT), 7...
... Beacon receiver (1% Ec), 11.21...
・・Up converter (U/C), 12°22・・・・
... Bin diode attenuator (PIN), 13°23...
...Power amplifier (PA). Agent Patent Attorney Minami Uchihara♀ 1 Kuni

Claims (1)

[Claims] a transmitting means for switching and transmitting the output of one of two transmitting systems, each of which is equipped with a level control circuit whose output level is controlled by a control signal; a level detecting means for detecting the transmission power of the transmitting means; A level control means for comparing the detected voltage of the level detection means with a reference voltage and controlling the level control circuit of the transmission system during transmission so that the two match, and a rain attenuation measuring means for detecting attenuation of radio waves due to rain. and a rain attenuation correction means for generating the reference voltage from the output of the rain attenuation measuring means and a reference voltage for setting the transmission power in a clear sky, wherein the level control means but when the detected voltage of the level detection means is within a first limit value predetermined with respect to the reference voltage, and the detected voltage is lower than the reference voltage by more than the first limit value. control the level control circuit when the detected voltage is within a predetermined second limit value with respect to the reference voltage, and control the level control circuit when the detected voltage does not satisfy the above condition. A transmission power control method characterized in that the transmission power control method is configured to stop the transmission and generate an alarm.