CN104883198A - Wireless communication module operating at 230MHz frequency band - Google Patents
Wireless communication module operating at 230MHz frequency band Download PDFInfo
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- CN104883198A CN104883198A CN201510234609.XA CN201510234609A CN104883198A CN 104883198 A CN104883198 A CN 104883198A CN 201510234609 A CN201510234609 A CN 201510234609A CN 104883198 A CN104883198 A CN 104883198A
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Abstract
The invention discloses a wireless communication module operating at a 230MHz frequency band. The wireless communication module comprises a transmitting module and a receiving module. The transmitting module of the wireless communication module uses a microcontroller chip to transmit processed data to a radio frequency chip in a serial interface communication manner and then the data is transmitted in the air in the form of electromagnetic waves. The receiving module transmits the acquired data to a master control chip via a serial interface. Analyzed and processed by the master control chip, the data is transmitted to a host computer in a serial port manner to be displayed in a visualized manner. Little interference is in the 230MHz frequency band. The wireless communication module is mainly used for distribution monitoring and wireless meter reading systems.
Description
Technical field
The present invention relates to wireless communication field, be specifically related to a kind of wireless communication module.
Background technology
Radio communication is a kind of communication mode utilizing the characteristic of electromagnetic wave signal aloft Free propagation to carry out information exchange, along with the high speed development of radio-frequency technique and integrated circuit technique, the requirement of people to radio communication is more and more higher, and short distance, convenient, cheap wireless communication technology are causing increasing concern.Therefore design a kind of transfer of data quick, antijamming capability is strong, and the wireless communication module that energy consumption is low is significant.
The frequency range used in domestic and international wireless communications application at present mainly comprises 433MHz, 470MHz, 915MHz and 2.4GHz.But these frequency ranges also cause co-channel interference more because being widely used, a large amount of co-channel interferences replaces man-made noise and other interference becomes the major constraints limiting wireless application.230MHz is the special frequency range of China's electric power system, and co-channel interference is less, effectively can improve the quality of communication.
Compared to high-frequency band, the signal of 230MHz frequency range is propagated farther, and diffracting power is stronger, improves the coverage of communication.The present invention utilizes CC1120 chip, and the wireless communication module that have developed a kind of 230MHz of being operated in frequency range, to realize radio communication, can meet the job requirement of electric power system, and this chip supports IEEE802.15.4g standard.
Summary of the invention
For solving problems of the prior art, the invention provides a kind of 230MHz wireless communication module supporting IEEE802.15.4g standard.Mainly realize the transmitting power of communication module, frequency shift (FS), transport communication distance, reliability communications, receiving sensitivity, the selection of a series of technical indicators of the aspect such as anti-interference and power consumption.
A kind of 230MHz wireless transmitter module supporting IEEE802.15.4g standard, comprise: micro controller module, radio-frequency communication module, serial communication interface, digital to analog converter, low pass filter, orthogonal mixer, power amplifier, impedance matching circuit, antenna, micro controller module obtains data, data send to the digit emitter in radio-frequency module after dissection process by serial communication interface, generate modulation signal, then send into digital to analog converter and form modulated-analog signal, High-frequency Interference is reduced by low pass filter, again by orthogonal mixer by modulated-analog signal and carrier signal superposition modulated to 230MHz radio frequency band, signal transmission is to after power amplifier, by the impedance matching circuit that load impedance is 50 Ω, eventually passing working frequency range is 230MHz, gain is that the omnidirectional antenna of 3.5dbi transmits in the form of an electromagnetic wave.
Described radio-frequency module adopts CC1120 radio frequency chip, and 230MHz emission of radio frequency signals is gone out by the antenna being 50 Ω by peripheral impedance matching circuit and impedance after radio frequency chip CC1120 process by the data in microcontroller.
A kind of 230MHz wireless receiving module supporting IEEE802.15.4g standard, comprise: micro controller module, radio-frequency module, balun circuit, low noise amplifier, frequency mixer, analog to digital converter, digital baseband receiver, baseband processor, serial communication interface, antenna, 230MHz antenna receives after single-ended radio frequency signal is converted to two orthogonal signalling by a balun circuit by signal and passes to CC1120 radio frequency chip, then signal power is amplified by low noise amplifier by signal, after having arrived frequency mixer, the frequency spectrum of high-frequency signal can be shifted to the frequency range of appropriate modulation, sampling is carried out to received signal and regeneration digital signal again by analog to digital converter, then, by the digital baseband receiver of numeric field, digital signal is processed, after baseband processor performs further filtration and signal transacting, pass to micro controller module finally by serial communication interface and dissection process is carried out to data.
A kind of 230MHz wireless communication module supporting IEEE802.15.4g standard, transmitting terminal comprises: micro controller module, radio-frequency communication module, serial communication interface, digital to analog converter, low pass filter, orthogonal mixer, power amplifier, impedance matching circuit, low pass filter, antenna, micro controller module obtains data, data send to the digit emitter in radio-frequency module after dissection process by serial communication interface, generate modulation signal, then send into digital to analog converter and form modulated-analog signal, High-frequency Interference is reduced by low pass filter, again by orthogonal mixer by modulated-analog signal and carrier signal superposition modulated to 230MHz radio frequency band, signal transmission is to after power amplifier, by the impedance matching circuit that load impedance is 50 Ω, eventually passing working frequency range is 230MHz, gain is that the omnidirectional antenna of 3.5dbi transmits in the form of an electromagnetic wave, receiver module comprises: micro controller module, radio-frequency module, balun circuit, low noise amplifier, frequency mixer, analog to digital converter, digital baseband receiver, baseband processor, serial communication interface, antenna, 230MHz antenna receives after single-ended radio frequency signal is converted to two orthogonal signalling by a balun circuit by signal and passes to CC1120 radio frequency chip, then signal power is amplified by low noise amplifier by signal, after having arrived frequency mixer, the frequency spectrum of high-frequency signal can be shifted to the frequency range of appropriate modulation, sampling is carried out to received signal and regeneration digital signal again by analog to digital converter, then, by the digital baseband receiver of numeric field, digital signal is processed, after baseband processor performs further filtration and signal transacting, pass to micro controller module finally by serial communication interface and dissection process is carried out to data.The center frequency point of wireless sending module and wireless receiving module, baud rate, channel is set to same parameters, the electromagnetic wave of the medium that both carry out communicating to be frequency range be 230MHz.First described sending module and receiver module configure the communication channel of same free time and empty buffer memory.
Present invention optimizes impedance matching circuit, make transmitting power reach+15dBm, frequency deviation is less than 50KHz, and effective communication distance reaches 2 kilometers, the receiving sensitivity of radio frequency chip can reach-123dBm, and ensure that the anti-interference of wireless communication module by electromagnetic compatibility test.
Accompanying drawing explanation
Fig. 1 is the structural representation of module of the present invention;
Fig. 2 software systems schematic diagram.
Embodiment
Below in conjunction with accompanying drawing, the invention will be further described;
A kind of 230MHz wireless transmitter module supporting IEEE802.15.4g standard, comprise: micro controller module, radio-frequency communication module, serial communication interface, digital to analog converter, low pass filter, orthogonal mixer, power amplifier, impedance matching circuit, antenna, micro controller module obtains data, data send to the digit emitter (TX BBP) in radio-frequency module after dissection process by serial communication interface, generate modulation signal, then send into digital to analog converter (DAC) and form modulated-analog signal, High-frequency Interference is reduced by low pass filter, again by orthogonal mixer by modulated-analog signal and carrier signal superposition modulated to 230MHz radio frequency band, signal transmission is to after power amplifier (PA), by the impedance matching circuit that load impedance is 50 Ω, eventually passing working frequency range is 230MHz, gain is that the omnidirectional antenna of 3.5dbi transmits in the form of an electromagnetic wave.
The 230MHz antenna of wireless receiving module receives after single-ended radio frequency signal is converted to two orthogonal signalling by a balun circuit by signal and passes to CC1120 radio frequency chip, then signal power is amplified by low noise amplifier (LNA) by signal, after having arrived frequency mixer, the frequency spectrum of high-frequency signal can be shifted to the frequency range of appropriate modulation, sampling is carried out to received signal and regeneration digital signal again by analog to digital converter (ADC), then, by the digital baseband receiver (RX BBP) of numeric field, digital signal is processed, after baseband processor performs further filtration and signal transacting, pass to micro controller module finally by serial communication interface and dissection process is carried out to data.The quality of communication can be observed by host computer.
When testing present channel wireless transceiver system performance, by the register of configuration CC1120 radio frequency chip, sending module (1) and receiver module (2) are set to same center frequency point, same baud rate, and same channel just can communicate.Sending module and receiver module are set up radio communication and are connected, and carry out transmission and the reception of data.The medium carrying out communicating is the electromagnetic wave of 230MHz frequency range.
First sending module and receiver module configure the communication channel of same free time and empty buffer memory.Sending module is first through serial ports initialization, after serial interface communication initialization and radio frequency chip initialization by dataframe to receiver module, first receiver module empties interruption, then wait for that FIFO (first-in first-out) memory is idle condition, then the verification of CRC cyclic redundancy check (CRC) code is carried out to data, if verification is not passed through, then abandon Frame, if verification is passed through, then parsings reception is carried out to this Frame, then pass to host computer by serial mode and print data intuitively.
Referring to Fig. 1, with an instantiation, enforcement of the present invention is further described, this wireless transceiver system, comprises sending module and receiver module.
With an instantiation, enforcement of the present invention is described in detail below.
Described microcontroller adopts the STM32F103RBT6 chip of ST Microelectronics, and it is mainly used to the data receiving, store and forward 230MHz frequency range, and the data message wherein needed is forwarded to host computer;
Described radio-frequency module have employed the CC1120 radio transceiver chip that TI company releases, and the RF radio-frequency (RF) transceiver of CC1120 is integrated with a highly configurable modulator-demodulator.Main control chip writes toward the register of CC1120 radio frequency chip inside the register parameters that value configures radio frequency chip by SPI interface, such as definition register FREQ1 and FREQ2 are the register of configuring chip centre frequency, 0x00 is write at FREQ1, FREQ2 writes 0x73 and centre frequency is configured to 230MHz, needs the register parameters of configuration to comprise centre frequency, transmitting power, frequency shift (FS), mode of operation, modulation/coding, baud rate, data packet format etc.
Power module adopts USB port to power, CH341 chip not only can make USB port serve as the function of serial ports, and be also the 3.3V power supply of whole circuit with stable by MAX8881 voltage stabilizing chip, MAX8881 is ultralow source current, low pressure difference linear voltage regulator, can provide the output up to 200mA.LED module controls LED, the state of instruction radio communication.USB module adopts CH341 chip, and CH341 is the connect chip of a usb bus, provides asynchronous serial port, LPT, parallel port and conventional 2 and 4 wire isosynchronous serial interface by usb bus.Under asynchronous serial port mode, CH341 provides interactively rate controlled signal and the conventional MODEM cues such as serial ports transmission is enable, serial ports ready for receiving, for being computer expansion asynchronous serial port, or common serial equipment is directly upgraded to usb bus.Under LPT mode, CH341 provides the standard of compatible USB related specifications and Windows operating system, USB LPT, for common parallel port printer is directly upgraded to usb bus.Under the mode of parallel port, CH341 provides 8 parallel-by-bit interfaces of EPP mode or MEM mode, under the environment not needing single-chip microcomputer/DSP/MCU, and direct inputoutput data.Debugging interface module is connected with master controller by J-TAG interface.On debugging software, single step execution can be carried out to it by this interface, breakpoint is set, the operation such as read-write chip internal register.
With reference to Fig. 2, first the main control part of sending module carries out serial ports initialization and SPI initialization, then by SPI control CC1120 radio-frequency module, carries out initialization to it.Initialization comprise arrange that its centre frequency is 230MHz, transmitting power is+15dBm, filter bandwidht is 25kHz, 2-FSK modulation, code rate is 1.2kbps etc., after initialization completes, data are transferred to radio-frequency module by SPI by main control module, radio-frequency module is after data processing, by data from antenna transmission out, carrier wave is the electromagnetic wave of 230MHz, sends LED successfully and has prompting.Receiver module also can through serial ports, SPI, radio frequency initialization, then whether receiver module inspection of having no progeny in removing is idle, receiver module carries out byte number inspection and CRC check to data after receiving the data of same channel sending module transmission, if verification is not passed through, then abandons Frame, if verification is passed through, then this Frame is resolved.Finally data-printing to host computer.Finally we can read the signal strength signal intensity RSSI of 230MHz frequency range from host computer, and the data such as packet loss are to understand the communication quality of present channel.
According to said structure, the present invention can configure relevant parameter, comprises and selects TX or RX pattern.When reception communicates with sending module, if the data that just can receive on the same channel of module are also shown corresponding information by host computer.Such as, the communication quality of the real-time packet receiving number shown at host computer by receiver module, received signal strength RSSI and test delivery and reception module, to select most suitable place to install communication node.
Claims (9)
1. support the 230MHz wireless transmitter module of IEEE802.15.4g standard for one kind, comprise: micro controller module, radio-frequency communication module, serial communication interface, digital to analog converter, low pass filter, orthogonal mixer, power amplifier, impedance matching circuit, antenna, it is characterized in that, micro controller module obtains data, data send to the digit emitter in radio-frequency module after dissection process by serial communication interface, generate modulation signal, then send into digital to analog converter and form modulated-analog signal, High-frequency Interference is reduced by low pass filter, again by orthogonal mixer by modulated-analog signal and carrier signal superposition modulated to 230MHz radio frequency band, signal transmission is to after power amplifier, by the impedance matching circuit that load impedance is 50 Ω, be 230MHz through working frequency range, gain is that the omnidirectional antenna of 3.5dbi transmits in the form of an electromagnetic wave.
2. wireless transmitter module according to claim 1, it is characterized in that, described radio-frequency module adopts CC1120 radio frequency chip, and 230MHz emission of radio frequency signals is gone out by the antenna being 50 Ω by peripheral impedance matching circuit and impedance after radio frequency chip CC1120 process by the data in microcontroller.
3. wireless transmitter module according to claim 2, it is characterized in that, the main control chip of micro controller module writes to the register of radio frequency chip inside the register parameters that value configures radio frequency chip by serial communication interface, definition register FREQ1 and FREQ2 is the register of configuring chip centre frequency, write 0x00, FREQ2 write 0x73 at FREQ1 and centre frequency is configured to 230MHz.
4. support the 230MHz wireless receiving module of IEEE802.15.4g standard for one kind, comprise: micro controller module, radio-frequency module, balun circuit, low noise amplifier, frequency mixer, analog to digital converter, digital baseband receiver, baseband processor, serial communication interface, antenna, it is characterized in that, antenna receives after single-ended radio frequency signal is converted to two orthogonal signalling by a balun circuit by signal and passes to CC1120 radio frequency chip in radio-frequency module, by low noise amplifier, signal power is amplified, after frequency mixer, by the frequency spectrum shift of high-frequency signal to predetermined modulation frequency range, carry out to received signal sampling and generating digital signal by analog to digital converter again, by the digital baseband receiver of numeric field, digital signal is processed, baseband processor filter further with signal transacting after, pass to micro controller module by serial communication interface and dissection process is carried out to data.
5. support the 230MHz wireless communication module of IEEE802.15.4g standard for one kind, comprise: wireless transmitter module, wireless receiving module, power management module, it is characterized in that, in wireless transmitter module, micro controller module obtains data, data send to the digit emitter in radio-frequency module after dissection process by serial communication interface, generate modulation signal, then send into digital to analog converter and form modulated-analog signal, High-frequency Interference is reduced by low pass filter, again by orthogonal mixer by modulated-analog signal and carrier signal superposition modulated to 230MHz radio frequency band, signal transmission is to after power amplifier, by the impedance matching circuit that load impedance is 50 Ω, be 230MHz through working frequency range, gain is that the omnidirectional antenna of 3.5dbi transmits in the form of an electromagnetic wave, in wireless receiving module, antenna receives after single-ended radio frequency signal is converted to two orthogonal signalling by a balun circuit by signal and passes to CC1120 radio frequency chip, then signal power is amplified by low noise amplifier by signal, after having arrived frequency mixer, the frequency spectrum of high-frequency signal can be shifted to predetermined modulation frequency range, carry out to received signal sampling and generating digital signal by analog to digital converter, by the digital baseband receiver of numeric field, digital signal is processed, after baseband processor performs further filtration and signal transacting, pass to micro controller module by serial communication interface and dissection process is carried out to data.
6. wireless communication module according to claim 5, is characterized in that, the center frequency point of wireless sending module and wireless receiving module, baud rate, and channel is set to same parameters, the electromagnetic wave of the medium that both carry out communicating to be frequency range be 230MHz.
7. wireless communication module according to claim 5, is characterized in that, first described sending module and receiver module configure the communication channel of same free time and empty buffer memory.
8. wireless communication module according to claim 5, it is characterized in that, the main control chip of micro controller module writes to the register of radio frequency chip inside the register parameters that value configures radio frequency chip by serial communication interface, definition register FREQ1 and FREQ2 is the register of configuring chip centre frequency, write 0x00, FREQ2 write 0x73 at FREQ1 and centre frequency is configured to 230MHz.
9. wireless communication module according to claim 5, it is characterized in that, power management module adopts USB port to power, wherein, USB module adopts CH341 chip, CH341 provides serial ports to send enable, the interactively rate controlled signal of serial ports ready for receiving and MODEM cue, is computer expansion asynchronous serial port, or serial equipment is directly upgraded to usb bus; Under the mode of parallel port, CH341 provides 8 parallel-by-bit interfaces of EPP mode or MEM mode, direct inputoutput data.
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| CN105704799A (en) * | 2016-01-22 | 2016-06-22 | 重庆邮电大学 | 510MHz wireless low-power-consumption communication module supporting IEEE802.15.4g standard |
| CN105871387A (en) * | 2016-03-25 | 2016-08-17 | 重庆邮电大学 | Single chip based dual-band (433/470MHz) wireless communication device synthesis manner |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105007092A (en) * | 2015-08-28 | 2015-10-28 | 重庆邮电大学 | 2.4 GHz wireless communication module supporting WIA-PA standard |
| WO2017101229A1 (en) * | 2015-12-14 | 2017-06-22 | Huawei Technologies Co., Ltd. | Reconfigurable multi-mode and multi-bands radio architecture and transceiver |
| US9992722B2 (en) | 2015-12-14 | 2018-06-05 | Huawei Technologies Canada Co., Ltd. | Reconfigurable multi-mode and multi-bands radio architecture and transceiver |
| CN105704799A (en) * | 2016-01-22 | 2016-06-22 | 重庆邮电大学 | 510MHz wireless low-power-consumption communication module supporting IEEE802.15.4g standard |
| CN105871387A (en) * | 2016-03-25 | 2016-08-17 | 重庆邮电大学 | Single chip based dual-band (433/470MHz) wireless communication device synthesis manner |
| CN106656249A (en) * | 2016-12-21 | 2017-05-10 | 广西放心源传媒有限公司 | System with information transmission function |
| CN110011943A (en) * | 2019-03-20 | 2019-07-12 | 珠海市杰理科技股份有限公司 | The adjustment method and device of electronic product commissioning device |
| CN109840230A (en) * | 2019-04-17 | 2019-06-04 | 华东师范大学 | Interface conversion equipment |
| CN109840230B (en) * | 2019-04-17 | 2024-05-10 | 华东师范大学 | Interface conversion device |
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