CN219780402U - Ad hoc network system based on satellite time service - Google Patents

Abstract

The utility model relates to the technical field of satellite timing, and discloses an ad hoc network system based on satellite timing, including a satellite base station, an ad hoc network base station, a radio station and communication equipment; the communication equipment includes a power amplifier module, a radio frequency module, and a baseband board. , switch module, power interface, data exchange interface, transceiver antenna interface; the satellite base station communicates with the ad hoc network base station through the satellite module to perform satellite timing, and the transceiver module of the ad hoc network base station communicates with the transceiver module of the radio station Connect, the radio station is communicatively connected to the transceiver antenna interface of the communication device. The utility model can solve the problem that time slot synchronization cannot be performed between self-organizing network base stations.

Description

A self-organizing network system based on satellite timing

Technical field

The utility model relates to the technical field of satellite timing, and in particular to a self-organizing network system based on satellite timing.

Background technique

TDMA, short for Time Division Multiple Access, is a technology widely used in radio communications. By dividing a frequency band into multiple time slots, each time slot allows only one user to send data, thereby achieving the purpose of multiple users communicating on the same frequency band. Since only one user can perform sending and receiving operations in a time slot, if time slot synchronization is not performed, different users will use the same time slot at the same time, causing interference and resulting in a decrease in communication quality. Gap synchronization is very important.

Most current radio communication equipment uses basic communication facilities for signal relay and time slot synchronization. After disasters such as earthquakes, floods, severe tropical storms, etc., fixed communication network facilities may be destroyed or unable to work properly. In this application scenario where every second counts, rapid deployment of emergency ad hoc networks can be used to replace basic communication facilities. However, in the ad hoc network, there are problems such as the time slot synchronization between base stations is often difficult, and the harsh environment has an offset effect on the crystal oscillator components of the ad hoc network equipment. Therefore, it is necessary to solve the problem that time slot synchronization cannot be performed between ad hoc network base stations.

Utility model content

The purpose of this utility model is to provide an ad hoc network system based on satellite timing, which can solve the problem that time slot synchronization cannot be performed between ad hoc network base stations.

In order to achieve the above purpose, the utility model provides an ad hoc network system based on satellite timing, including a satellite base station, an ad hoc network base station, a radio station and communication equipment; the communication equipment includes a power amplifier module, a radio frequency module, a baseband board, Switch module, power interface, data exchange interface, transceiver antenna interface; the satellite base station communicates with the ad hoc network base station through the satellite module to perform satellite timing, and the transceiver module of the ad hoc network base station is communicatively connected with the transceiver module of the radio station , the radio station is communicatively connected to the transceiver antenna interface of the communication device. The radio station decodes the signaling by the computing unit to estimate the starting time of air transmission and adjusts the local clock edge. The satellite module included in the switch module is used for the communication device. Synchronization and frequency calibration, time slot segmentation.

In some embodiments, the ad hoc network base station receives the clock signal transmitted by the satellite base station, performs time slot calibration, and sends a heartbeat packet containing synchronization time information to the radio station.

In some embodiments, after completing time synchronization, the radio station distinguishes talk groups through different time slots in the same frequency band.

In some embodiments, the satellite module included in the switch module provides precise pulses through Beidou/GPS dual-mode positioning.

In some embodiments, the communication device further includes a voltage controlled oscillator, a D/A converter, a delay, and a 1/10M frequency divider.

In some embodiments, the satellite module included in the switch module receives the second pulses from the satellite base station and performs phase detection, filtering, aging compensation, PI control, D/A conversion, frequency modulation, frequency division, and delay processing to perform second timing. , calibrate the crystal oscillator of the communication device.

The embodiment of the present utility model is an ad hoc network system based on satellite timing. Compared with the existing technology, its beneficial effects are:

The self-organizing network system based on satellite timing completes the synchronization between base stations through satellite timing, ensuring the high-precision requirements for signal transmission time for same-frequency simulcast; communication equipment only needs to add the corresponding satellite module to perform time slot synchronization; communication The equipment all uses crystal oscillators to generate frequency signals. The crystal oscillators will shift with changes in temperature and time. Satellite timing can be used to calibrate the frequency shift of the crystal oscillators, which is more accurate than traditional communication network equipment's method of solving crystal oscillator shifts. efficient.

Description of the drawings

Figure 1 is a block diagram of the composition and connection of an ad hoc network system based on satellite timing according to an embodiment of the present invention;

Figure 2 is a process of reducing delay by a radio station according to an embodiment of the present invention;

Figure 3 is a process diagram of the ad hoc network base station using satellites for timing according to the embodiment of the present invention;

Figure 4 is a schematic diagram of crystal oscillator calibration based on satellite timing communication equipment according to an embodiment of the present invention.

Detailed ways

In order to make the above objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation modes of the present invention will be described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth to facilitate a thorough understanding of the present invention. However, the present utility model can be implemented in many other ways different from those described here. Those skilled in the art can make similar improvements without violating the connotation of the present utility model. Therefore, the present utility model is not limited to the specific embodiments disclosed below. limit.

In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", etc. are based on the orientation or positional relationship shown in the drawings, and only It is intended to facilitate the description of the present invention and simplify the description, but does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

In addition, the terms “first” and “second” are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Therefore, features defined as "first" and "second" may explicitly or implicitly include at least one of these features. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically limited.

As shown in Figure 1, an ad hoc network system based on satellite timing according to the preferred embodiment of the present invention includes a satellite base station 1, an ad hoc network base station 2, a radio station 3 and a communication device 4; the communication device 4 includes a power amplifier module, radio frequency module, baseband board, switch module, power interface, data exchange interface, transceiver antenna interface; the satellite base station 1 communicates with the ad hoc network base station 2 through the satellite module to perform satellite timing, and the transceiver of the ad hoc network base station 2 The module is communicatively connected to the transceiver module of the radio station 3, and the radio station 3 is communicatively connected to the transceiver antenna interface of the communication device 4. The radio station 3 estimates the start time of air transmission and adjusts the local clock by decoding the signaling through the computing unit. On the edge, the switch module contains a satellite module, which is used for synchronization, frequency calibration and time slot division of communication equipment.

In a specific embodiment, the ad hoc network base station receives the clock signal transmitted by the satellite base station, performs time slot calibration, and sends a heartbeat packet containing synchronization time information to the radio station.

In a specific embodiment, after completing time synchronization, the radio station distinguishes talk groups through different time slots in the same frequency band.

In a specific embodiment, the satellite module included in the switch module provides precise pulses through Beidou/GPS dual-mode positioning.

In a specific embodiment, the communication device further includes a voltage controlled oscillator, a D/A converter, a delay, and a 1/10M frequency divider.

In a specific embodiment, the satellite module included in the switch module receives the second pulses from the satellite base station and performs phase detection, filtering, aging compensation, PI control, D/A conversion, frequency modulation, frequency division, and delay processing to perform second timing. , calibrate the crystal oscillator of the communication device.

It should be noted that each ad hoc network base station needs to have the function of receiving satellite timing signals: when the base station receives the satellite timing signals, it needs to synchronize the local clock based on the timing signals. Since time division multiple access is used to divide channels, The requirements for time accuracy are higher. There is a certain delay when the receiver receives the satellite timing signal, so the receiver needs extremely high timing accuracy. The timing accuracy of the receiver is mainly affected by the characteristics of the crystal oscillator, the clock compensation characteristics of the receiver and the positioning accuracy characteristics. The satellite module used in this system has the function of eliminating satellite clock differences; after synchronizing the local clock, the ad hoc network base station needs to The station broadcasts heartbeat packet data. The heartbeat packet data contains synchronization messages and is used to notify the radio station of its current time. There is a delay in the process of broadcasting the heartbeat packet by the ad hoc network base station. This delay cannot be avoided, but delay prediction can be used. The method of estimation reduces the error in the time slot caused by the delay: the signal transmitted by the ad hoc network base station in the air carries the time slot mark, and the radio station performs clock calibration based on the received heartbeat packet data. The calibration process is divided into two steps. : After decoding the signaling, the starting time of signal transmission in the air is estimated based on the time of decoding the signaling, and the clock is adjusted to the same edge as the base station. The adjustment of the edge ensures that the edge of the receiving end is consistent with the main transmitting end, eliminating the localization of the radio station. Small errors in the clock; unify the time slot marks according to the time slot number in signaling to ensure that the correct time slot is used for forwarding logical services. In this way, the transmitting end and the receiving end are at the same time. This method can reduce the error to the nanosecond level and meet the communication needs of direct time division multiple access in ad hoc networks.

After receiving the synchronization message, the radio station needs to synchronize its own clock according to the clock information in the message. When all radio stations have completed clock synchronization, they can communicate according to the pre-agreed time slot sequence, thereby avoiding time slot conflicts and interference.

When the crystal oscillator of a communication device is inaccurate, communication errors and instability can result. In order to ensure accurate and stable communication, the crystal oscillator must be calibrated. The process of crystal oscillator calibration using the satellite timing system is as follows: the transceiver module uses the satellite timing signal to obtain accurate time information; compares the obtained satellite time information with the actual time in the communication equipment, and adjusts the frequency of the crystal oscillator based on the comparison results. Until it is calibrated to a more accurate level; since the crystal oscillator in communication equipment will gradually drift over time and other reasons, regular calibration is required to ensure the reliability of communication.

In summary, the embodiment of the present invention provides an ad hoc network system based on satellite timing, which completes synchronization between base stations through satellite timing, ensuring high-precision requirements for signal transmission time for same-frequency simulcast; communication equipment only needs Adding the corresponding satellite module can perform time slot synchronization; communication equipment uses crystal oscillators to generate frequency signals. The crystal oscillators will offset with changes in temperature and time. The frequency offset of the crystal oscillators can be calibrated using satellite timing, which is different from traditional It is more effective than the communication network equipment to solve the crystal oscillator offset.

The above are only preferred embodiments of the present invention. It should be pointed out that those skilled in the art can make several improvements and substitutions without departing from the technical principles of the present invention. These improvements and replacement should also be regarded as the protection scope of the present utility model.

Claims (6)

1. An ad hoc network system based on satellite timing, characterized in that it includes a satellite base station, an ad hoc network base station, a radio station and communication equipment; the communication equipment includes a power amplifier module, a radio frequency module, a baseband board, a switch module, and a power supply interface, data exchange interface, transceiver antenna interface; the satellite base station communicates with the ad hoc network base station through the satellite module to perform satellite timing, the transceiver module of the ad hoc network base station is communicatively connected with the transceiver module of the radio station, and the radio station is connected with the transceiver module of the radio station. The transceiver antenna interface of the communication device is connected for communication. The radio station decodes the signaling by the computing unit to estimate the starting time of air transmission and adjusts the local clock edge. The satellite module included in the switch module is used for synchronization and frequency of the communication device. Calibration,slot segmentation. 2. The ad hoc network system based on satellite timing according to claim 1, characterized in that: the ad hoc network base station receives the clock signal transmitted by the satellite base station to calibrate the time slot, and issues synchronization time information. heartbeat packet to the radio station. 3. The ad hoc network system based on satellite timing according to claim 1 or 2, characterized in that: after the radio station completes time synchronization, the talk groups are distinguished by different time slots in the same frequency band. 4. The self-organizing network system based on satellite timing according to claim 1, characterized in that the satellite module contained in the switch module provides accurate pulses through Beidou/GPS dual-mode positioning. 5. The ad hoc network system based on satellite timing according to claim 1, characterized in that the communication equipment further includes a voltage controlled oscillator, a D/A converter, a delay, and a 1/10M frequency divider. 6. The self-organizing network system based on satellite timing according to claim 1, characterized in that the satellite module included in the switch module receives the second pulse of the satellite base station and undergoes phase detection, filtering, aging compensation, and PI control. D/A conversion, frequency modulation, frequency division, and delay processing are performed in seconds to calibrate the crystal oscillator of the communication equipment.