KR100212200B1 - Modulation control method in a pager data transmission system - Google Patents

Abstract

The present invention relates to a modulator control method of a radio call data transmission system applicable to communication using satellites.

The present invention is composed of a central earth station, a network management system and a terminal earth station in consideration of the fact that the control of the modulator of the central earth station of the radio call data transmission system is performed only by manual setting of a conventional operator, which communicates using a geostationary satellite. In the radio call data transmission system, it is possible to control the modulator more effectively by allowing not only manual control by the operator but also control of the modulator by the network management system.

Description

Modulator Control Method of Wireless Call Data Transmission System

1 is a system block diagram for modulator operation in a typical paging data transmission system.

2 is a view for explaining the operation of the modulator in the radio call data transmission system according to the present invention.

* Explanation of symbols for main parts of the drawings

1: Modulator 2: NMS Module

3: buffer 4: main module

The present invention relates to a satellite communication system using satellites, and to a modulator control method of a radio call data transmission system for operating a modulator of a central earth station in a pagersat earth station (PAGES) system using a green light satellite. will be.

In general, a radio call data transmission earth station communication system using a geostationary satellite includes a pagersat central earth station (hereinafter referred to as PCES) of a radio call data transmission earth station and a pagersat remote earth station of a radio call data transmission earth station. Hereinafter referred to as PRES) and a network management system (hereinafter referred to as NMS).

Among them, PCES has a modulator for modulating the channel frequency for transmission.

FIG. 1 shows a system block diagram for operating a modulator in a typical paging data transmission system, which controls the modulator 1, the NMS module 2, and the NMS module 2 for channel frequency modulation for transmission. A buffer (3) where commands are temporarily stored, a main module (4) for overall control of the system, a binary coded decimal (BCD) switch (BCD SW) and a dip switch (to determine the status of the channel selection and modulator 1) DIP SW).

In such a system, the control of the modulator 1 was performed according to the operator setting the BCD switch (BCD SW) value.

Therefore, in the related art, the control of the modulator is performed only by manual setting of an operator, which is very inconvenient in terms of network management.

The present invention has been made in view of the above, and the radio call data transmission for controlling the modulator by NMS as well as manual control by the operator when controlling the modulator of the central earth station of the radio call data transmission system enables more effective control of the modulator. It is an object of the present invention to provide a method for controlling a modulator of a system.

In order to achieve the above object, the present invention is a radio call data earth station communication system composed of PCES, NMS, and PRES to communicate using geostationary orbit satellites. It is characterized by controlling the operation of the modulator efficiently by controlling in the remote mode.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

First, the present invention is performed in the system as shown in FIG. 1, which will be described together with FIG.

First, the initialization process is performed when the power is turned on.

Initialization process first determines the baud rate of the channel from the dip switch (DIP SW).

When the initialization process is performed, the channel number and the state of the modulator 1 are read through the dip switch (DIP SW) and the BCD switch (BCD SW).

If all control of the modulator 1 is in a local mode which is manually performed by the operator, the modulator 1 reads the BCD switch (BCD SW) value set by the operator, and the BCD switch in the remote mode. The (BCD SW) value is ignored and the transmission frequency value sent by the NMS module 2 is read.

Then, the transmission channel frequency is calculated using the channel number, and if the channel number is within the prescribed range, the data to be sent to the frequency synthesizer in the modulator 1 using the calculated transmission channel frequency (3 bit address, 4 bit data, 2 bit). Calculates the strobe), updates the database, and sends it to the frequency synthesizer to ensure that the control of the modulator 1 meets the requirements.

Here, the calculation method of the channel frequency used to obtain the satellite IF frequency 52-88 used in the satellite is 70 + (Channel number -360) 0.05 , 0.05 at this time (5 ) Is 5 Means to select by unit.

In addition, the prescribed range means 0-720, and when it is 0, 52 At 88 Becomes

On the other hand, when the local mode is set during normal operation and the operator changes the BCD switch (BCD SW) or when the transmission channel frequency is changed by the NMS module 2 in the remote mode, the transmission channel mute is declared.

In this case, the transmission channel mute means to close the transmission channel by turning off a hardware-configured switch. When the output of the mute switch buffer 3 is 1, the transmission channel is muted, and when 0, the mute is released.

Then, the transmission channel frequency is recalculated and transmitted to the frequency synthesizer, and generates an alarm when an abnormality occurs in the modulator 1.

Here, the alarm (alarm) can be generated using, for example, a frequency synthesizer alarm, an AGC (Auto Gain Control) alarm, a Watchdog alarm used for the CPU, and the like.

Then, when all alarms are cleared, the transmission channel frequency mute is released and again the transmission channel frequency is transmitted.

As described above, the present invention can effectively control the modulator in the remote mode by the NMS and the local mode by the operator, thereby improving the operation method and quality of the satellite communication system.

Claims (1)

In the control method of a radio call data transmission system composed of a central earth station, a network management system, and a terminal earth station, which communicates using a geostationary satellite, after the initialization process, a channel number and a state of a modulator are read through a dip switch and a BCD switch. The first step is to read the BCD switch value if all the control of the modulator is in local mode, and to read the transmission frequency value sent from the NMS module in remote mode, calculate the transmission channel frequency using the channel number, and define the channel number. The second step of calculating the data to be sent to the frequency synthesizer in the modulator using the calculated transmission channel frequency, updating the database and transmitting the data to the frequency synthesizer, and setting the local mode to normal operation of the BCD switch. Channel is changed by NMS module in case of A third step of declaring a transmission channel mute when the wave number is changed, a fourth step of recalculating and transmitting the transmission channel frequency to a frequency synthesizer, generating an alarm when an abnormality of the modulator occurs, and muting the transmission channel frequency when all alarms are released. Is released, and the transmission channel frequency is transmitted in a fifth step.