The Design Of 2.4GHz Wireless Remote Control System

In today's information age,wireless communication technology has been rapid development,radio communication in people's lives everywhere is almost involved in all areas of society.At the same time wireless communication equipment is widely used in aircraft model equipment.2.4G RF technology in the application of the model system focused on the design of the system in the frequency hopping technology.Modulation has gone through AM,PPM,PCM,etc.,but also on the aircraft model system reliability,stability,convenience put forward higher requirements,it is very important to study.At present,the research of model aircraft remote control mainly focuses on the control mode of aircraft model.There is little research on frequency hopping technology,and the reliability and stability of communication system depends on the performance of frequency hopping system.Design for frequency hopping is also a frontier issue.In this paper,the design of the whole system is started by theoretical calculation design,and then the software simulation and simulation,and finally through the hardware implementation.In the paper,the author first introduces the author's design idea,selects the spread spectrum communication technology among the many communication technologies,and the frequency hopping communication technology in the spread spectrum communication as the core of the thesis.The principle of frequency hopping communication and the modulation method,the modulation of the spectrum moved to the frequency of jump to avoid interference.This paper focuses on the design of digital frequency synthesizer and frequency hopping sequence.The frequency hopping sequence is designed to ensure that the information is not intercepted.The design of the frequency hopping sequence is limited by theory,and the jump system is used on the 2.4G frequency baseband.Pseudo-random sequence design of 64 MHz in the choice of 32 frequency hopping points and random order of a frequency point to form a band to ensure that within a certain period of time to repeat,a short time to obtain the purpose of spreading.Then use the DC digital synthesizer AD9854 chip,a standard frequency is built into a number of different hopping frequency,the frequency of multiple transitions and pseudo-random sequence to control the carrier signal to achieve safe and reliable communication.The innovation of the thesis is to design the frequency hopping sequence.The random sequence is superimposed on the cryptographic program designed by the random sequence,and the cryptographic program and the pseudo-random sequence are convoluted when the signal is restored.This paper uses the frequency hopping design method at 2.4GHz.Hardware,in the Altium designer design and development platform to complete the circuit schematic design and printing.The system design section gives the sending and receiving flowcharts,PCB printed circuit boards,experimental results and experimental graphics.And lists the main program and application program on NRF51822.After the design process and the system connection,into the MATLAB simulation simulation,and then to the scene of the test analysis can be concluded that the whole system has high reliability,anti-interference ability,cost-effective advantages.