Automatic frequency hopping image transmission communication system

Abstract

The utility model provides an automatic frequency hopping image transmission communication system, which comprises at least one host and a plurality of slaves in wireless communication with the host, and the host and the slaves respectively comprise a frequency hopping communication circuit. The frequency hopping communication circuit is composed of a chip which supports the fastest 100 hops per second and is provided with 80 channels, the channel interval is 30 kHz, the self-correlation coefficient is 0.4, the mutual relation is 0.5, the frequency hopping sequence length is at least 80, and the synchronization time is three frames of 10 milliseconds. The host and the slave of the image transmission communication system adopt the chip supporting the frequency hopping technology for communication, single-frequency communication is not used any more, so that interference signals are difficult to aim at specific frequencies to interfere, the stability and the reliability of communication are improved, the chip supporting the frequency hopping technology can send and receive signals at different frequencies, and the communication efficiency is improved. And the influence of signal fading and multipath effect is effectively avoided.

Description

TECHNICAL FIELD

[0001] The utility model relates to wireless communication technical field especially relates to a kind of automatic frequency hopping map transmission communication system. BACKGROUND

[0002] Map transmission communication system is a kind of system for transmitting image and video signal, is widely used in unmanned aerial vehicle, monitoring, remote medical treatment and other need real-time video transmission field, the image collected is transmitted to receiving end by wireless signal or wired signal, to realize real-time viewing and monitoring.

[0003] The existing map transmission communication system usually adopts single-frequency communication mode, on the one hand, single-frequency communication is susceptible to interference from other radio equipment during signal transmission, especially in the electromagnetic environment complex area, the signal of other wireless equipment can interfere with single-frequency communication, affect communication quality, on the other hand, in the city with high-rise buildings, coverage blind area or blind spot can be encountered, signal coverage is not reached in these areas, leading to communication interruption or quality degradation. SUMMARY

[0004] The utility model provides a kind of automatic frequency hopping map transmission communication system to solve the problem that the communication quality of map transmission communication system in prior art needs to be improved.

[0005] The utility model provides a kind of automatic frequency hopping map transmission communication system, including at least one host computer and several slave computers for wireless communication with each host computer, the host computer and the slave computer all include frequency hopping communication circuit, the frequency hopping communication circuit is by the chip that supports fastest 100 jumps per second, with 80 channels, channel spacing 30 kHz, autocorrelation coefficient 0.4, cross correlation 0.5, frequency hopping sequence length is at least 80, synchronization time is three frames 10 milliseconds.

[0006] According to the automatic frequency hopping map transmission communication system provided by the utility model, the frequency hopping communication circuit includes frequency hopping chip and transceiver chip connected with the frequency hopping chip.

[0007] According to the automatic frequency hopping map transmission communication system provided by the utility model, the TXN pin of the frequency hopping chip is connected to the TD- pin of the transceiver chip through common mode filter, the TXP pin of the frequency hopping chip is connected to the TD+ pin of the transceiver chip through common mode filter, the RXN pin of the frequency hopping chip is connected to the RD- pin of the transceiver chip through common mode filter, and the RXP pin of the frequency hopping chip is connected to the RD+ pin of the transceiver chip through common mode filter, and the TXN pin, TXP pin, RXN pin and RXP pin are all connected with pull-up resistor and pull-down capacitor.

[0008] The nFDX_LED pin, the nLNKA_LED pin and the nSPD_LED pin of the frequency hopping chip are connected with an LED display screen.

[0009] The XI pin and the XO pin of the frequency hopping chip are connected with a crystal oscillator.

[0010] The frequency hopping chip is connected with 3.3V voltage and 12V voltage.

[0011] The CT pin of the transceiver chip is connected with the common end of a capacitor and an inductor through a resistor, one end of the inductor is connected with 3.3V voltage, and the other end of the capacitor is grounded.

[0012] The automatic frequency hopping image transmission communication system provided by the utility model adopts the chip supporting frequency hopping technology to communicate between the host and the slave of the image transmission communication system, and single frequency communication is not used any more, so that the interference signal is difficult to interfere with the specific frequency, the stability and reliability of the communication are improved, the chip supporting frequency hopping technology can send and receive signals on different frequencies, and the influence of signal fading and multipath effect is effectively avoided. BRIEF DESCRIPTION OF DRAWINGS

[0013] In order to more clearly illustrate the technical scheme in the utility model or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or the prior art description, and obviously, the drawings in the following description are some embodiments of the utility model, and for those skilled in the art, other drawings can be obtained according to these drawings without creative labor.

[0014] Figure 1 It is the principle block diagram of the automatic frequency hopping image transmission communication system provided by the utility model;

[0015] Figure 2 It is the circuit principle diagram of one embodiment of the frequency hopping communication circuit provided by the utility model;

[0016] Figure 3 It is the frequency hopping frame synchronization schematic view provided by the utility model.

[0017] Marked with a figure:

[0018] 1-host, 2-slave, 3-frequency hopping communication circuit. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical scheme and advantages of the utility model more clear, the technical scheme in the utility model will be described clearly and completely in combination with the drawings in the utility model below, obviously, the described embodiments are part of the embodiments of the utility model, instead of all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the person skilled in the art without making creative labor belong to the protection scope of the utility model.

[0020] In the description of the embodiments of the present application, it should be noted that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the embodiments of the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the present application. In addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0021] In the description of the embodiments of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "connected", "connected" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected, it can be mechanically connected, or it can be electrically connected, it can be directly connected, or indirectly connected through an intermediate medium. For the person skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0022] In the embodiments of the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature, which can be direct contact between the first and second features, or indirect contact between the first and second features through an intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be directly above or obliquely above the first feature, or only indicate that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be directly below or obliquely below the first feature, or only indicate that the horizontal height of the first feature is less than that of the second feature.

[0023] In the description of the specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example" or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples without contradiction.

[0024] The following will be described in combination with Figures 1-3 The automatic frequency hopping image transmission communication system provided by the utility model will be described in detail.

[0025] Figure 1 It is the principle block diagram of the automatic frequency hopping image transmission communication system provided by the utility model, referring to Figure 1 The utility model provides a kind of automatic frequency hopping image transmission communication system, including at least one host computer 1 and several slave machines 2 with each described host computer 1 wireless communication, host computer 1 refers to ground station, slave machine 2 refers to unmanned aerial vehicle, the host computer 1 and the slave machine 2 all include frequency hopping communication circuit 3, the frequency hopping communication circuit 3 is made of chip with 80 channels, channel spacing 30 kHz, autocorrelation coefficient 0.4, cross correlation 0.5, frequency hopping sequence length is at least 80, synchronization time is three frames 10 milliseconds, supports fastest 100 jumps per second, each frame is equal to 5 subframes.

[0026] As shown in Figure 2 As an embodiment, the frequency hopping communication circuit 3 includes a frequency hopping chip and a transceiver chip connected to the frequency hopping chip. The TXN pin of the frequency hopping chip is connected to the TD- pin of the transceiver chip through a common mode filter, the TXP pin of the frequency hopping chip is connected to the TD+ pin of the transceiver chip through a common mode filter, the RXN pin of the frequency hopping chip is connected to the RD- pin of the transceiver chip through a common mode filter, the RXP pin of the frequency hopping chip is connected to the RD+ pin of the transceiver chip through a common mode filter, and the TXN pin, TXP pin, RXN pin and RXP pin are all connected with pull-up resistor and pull-down capacitor. The nFDX_LED pin, nLNKA_LED pin and nSPD_LED pin of the frequency hopping chip are connected with LED display screen. The XI pin and XO pin of the frequency hopping chip are connected with crystal oscillator. The frequency hopping chip is connected with 3.3V voltage and 12V voltage. The CT pin of the transceiver chip is connected with the common end of capacitor and inductor through resistance, the other end of inductor is connected with 3.3V voltage, and the other end of capacitor is grounded.

[0027] The working process of the utility model will be described below in combination with the drawings, and it should be noted that the utility model does not improve the process of frequency hopping technology.

[0028] When the host 1 causes the error rate of the received signal to deteriorate due to various interferences or transmission distances, etc., the automatic frequency hopping threshold is triggered at this time, and the automatic frequency hopping mode is started, first, the best frequency point is traversed in the frequency hopping list through the RSSI and PER index parameters, and then the frequency hopping frequency point corresponding serial number and some conventional configuration parameters are packaged, and the transceiver chip is used to send to the slave 2 in the special subframe of N+1 frame. After the slave 2 receives the frequency hopping instruction started by the host 1, the transceiver chip is used to reply to the host 1 in N+2 frame and inform the next frame to start the frequency hopping switching, and the host 1 and the slave 2 perform the frequency hopping configuration according to the mutual agreement, and the frequency of the frequency synthesizer is changed according to the mutual agreement in the N+3 frame, and the frequency hopping switching is completed in N+3.

[0029] The frequency hopping communication circuit 3 mainly includes the following functions:

[0030] 1. Screening available channels: the physical layer selects an optimal channel through PER, BER, SNR, RSSI and other indicators.

[0031] 2. Frequency hopping sequence generation: using a pseudo-random code sequence for frequency shift keying, the carrier frequency is constantly changed. The frequency point of each carrier is changed in a pre-set group of frequency points according to a certain frequency hopping sequence with the change of frame.

[0032] 3. Synchronization: the host 1 and the slave 2 are synchronized after three frame handshakes.

[0033] 4. Synthesis of frequency hopping frequency: the frequency synthesizer is used to change to the frequency hopping frequency in the third frame, and the frequency hopping switching is started.

[0034] The utility model can realize the automatic control of the working channel, so that the ground station works in the automatically set frequency domain, thereby reducing the influence of environmental interference on the performance of the ground station, and improving the accuracy and stability.

[0035] It can be understood that the utility model uses the chip supporting frequency hopping technology to communicate between the host 1 and the slave 2 of the image transmission communication system, and no longer uses single frequency communication, so that the interference signal is difficult to interfere with the specific frequency, and the stability and reliability of the communication are improved. The chip supporting frequency hopping technology can send and receive signals at different frequencies, effectively avoiding the influence of signal fading and multipath effect. By using multiple frequencies, more data can be transmitted without increasing the bandwidth, and the utilization rate of frequency spectrum resources is improved. Since the frequency is constantly changing, it is difficult to be intercepted and cracked, thereby improving the confidentiality of the communication.

[0036] It should be finally pointed out that: the above examples are only used to illustrate the technical solutions of the utility model, and not to limit them; although the utility model has been explained in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement to part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the utility model.

Claims

1. An automatic frequency hopping image communication system characterized by, The system comprises at least one master and several slaves in wireless communication with each master, and each of the master and the slave comprises a frequency hopping communication circuit, which is composed of a chip supporting a maximum of 100 hops per second, 80 channels, a channel interval of 30 kHz, an autocorrelation coefficient of 0.4, a cross-correlation of 0.5, a frequency hopping sequence length of at least 80, and a synchronization time of three frames of 10 ms.

2. The automatic frequency hopping image communication system of claim 1, wherein, The frequency hopping communication circuit comprises a frequency hopping chip and a transceiver chip connected with the frequency hopping chip.

3. The automatic frequency hopping image communication system of claim 2, wherein, The TXN pin of the frequency hopping chip is connected to the TD- pin of the transceiver chip through a common mode filter, the TXP pin of the frequency hopping chip is connected to the TD+ pin of the transceiver chip through a common mode filter, the RXN pin of the frequency hopping chip is connected to the RD- pin of the transceiver chip through a common mode filter, and the RXP pin of the frequency hopping chip is connected to the RD+ pin of the transceiver chip through a common mode filter, and the TXN pin, the TXP pin, the RXN pin and the RXP pin are connected with pull-up resistors and pull-down capacitors.

4. The automatic frequency hopping image communication system of claim 2, wherein, The nFDX_LED pin, the nLNKA_LED pin and the nSPD_LED pin of the frequency hopping chip are connected with LED display screens.

5. The automatic frequency hopping image communication system of claim 2, wherein, The XI pin and the XO pin of the frequency hopping chip are connected with crystal oscillators.

6. The automatic frequency hopping image communication system of claim 2, wherein, The frequency hopping chip is connected with a 3.3V voltage and a 12V voltage.

7. The automatic frequency hopping image communication system of claim 2, wherein, The CT pin of the transceiver chip is connected with a common end of a capacitor and an inductor through a resistor, the other end of the inductor is connected with a 3.3V voltage, and the other end of the capacitor is grounded.

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