随着社会的发展，时代的进步，防丢器将在人们日常生活中发挥着越来越大的作

With the development of society and the progress of the times, anti-lost devices will play an increasingly important role in people's daily lives. Therefore, many experts and scholars have studied, analyzed and designed the anti-lost device. In 2000, Zhang Zhaohui designed an anti-lost device with the UM3758-108A codec chip as the core. When the master and slave units exceed the specified range, an audible and visual alarm will appear. In 2010, Liu Mige and Wang Lu designed an anti-lost device, which is based on the PT2262 / PT2272 codec integrated chip. The anti-lost device not only has anti-lost function, but also has a search function. In 2014, Guo Mingming, Han Yang and others studied and designed a two-way anti-lost device based on Bluetooth technology. The anti-lost device overcomes the problem of the single anti-lost alarm of the original anti-lost device and develops a new type of anti-lost device. <br>The main component of the anti-lost device is the wireless transmission distance. In this paper, we study the short-range anti-lost device, 2.4GHz wireless technology, which is a global frequency band. This frequency band is currently widely used in indoor occasions such as wireless construction and wireless broadband routers. It is a short-distance wireless transmission technology. Nowadays, there are multiple standard wireless protocols in the 2.4GHz frequency band. They have long transmission distances and strong anti-interference. Therefore, we must ensure that there is sufficient anti-interference and maintain data continuity in the 2.4GH band. <br>nRF24L01 can easily build a wireless network due to the ANT protocol. ANT's wireless personal local area network communication technology maintains data integrity and has the advantages of low consumption and low cost. nRF24L01 is a wireless communication chip using FSK modulation, it can be point-to-point and 1 to n high-speed communication. The MCU only needs to provide 5 ordinary pins and an interrupt pin to the nRF24L01 wireless module to realize the communication function. So it is very simple for the MCU system to build wireless communication function using nRF24L01.

With the development of society and the progress of the times, the anti-thrower will play an increasingly important role in people's daily life. Therefore, many experts and scholars have studied, analyzed and designed the anti-thrower. In 2000, Zhang Zhaohui designed a UM3758-108A codec chip as the core of the anti-thrower, when the mother and sub-machine exceed the prescribed range will appear sound and light alarm. In 2010, Liu Mige and Wang Lu designed an anti-thrower, which is based on the PT2262/PT2272 codec integration chip. The anti-thrower not only has anti-throw function, but also has the lookup function. In 2014, Guo Mingming, Han Yang and others studied and designed a two-way anti-thrower based on Bluetooth technology, which overcomes the problem of the original anti-thrower single sound and light alarm, and developed a new type of anti-thrower.<br>The main componentof of the anti-thrower is the wireless transmission distance, we study this paper is a short-range anti-thrower, 2.4GHz wireless technology, it is a global frequency band, the development of products with global versatility, a variety of wireless products can use this band, is currently widely used in wireless construction and wireless broadband routers and other indoor occasions. It is a short-range wireless transmission technology, now in the 2.4GHz band has a variety of standard wireless protocols, they transmit a long distance, strong anti-jamming. So we want to make sure that there is enough interference resistance and data continuity on the 2.4GH band.<br>nRF24L01 Is a convenient wireless network for the SAKE of the ANT protocol. ANT's wireless personal LAN communication technology keeps the data complete and has the advantage of low consumption and low cost. the nRF24L01 is a wireless communication chip modulated by FSK, which can be point-to-point and 1-to-n high-speed communication. The MCU only needs to provide five normal pins and one interrupt pin to the nRF24L01 wireless module for communication. Therefore, mcU system to build wireless communication function using nRF24L01 is very simple.

With the development of society and the progress of the times, the anti loss device will play an increasingly important role in people's daily life. Therefore, many experts and scholars have studied, analyzed and designed the anti loss device. In 2000, Zhang Chaohui designed an anti loss device with um3758-108a codec chip as the core. When the master and slave exceed the specified range, the sound and light alarm will appear. In 2010, Liu Mige and Wang Lu designed a loss preventer, which takes PT2262 / PT2272 codec integrated chip as the core. The anti loss device not only has the anti loss function, but also has the search function. In 2014, Guo Mingming, Han Yang and others researched and designed a two-way anti loss device based on Bluetooth technology, which overcomes the problem of single sound and light alarm of the original anti loss device and develops a new anti loss device.<br>The main component of the loss preventer is the wireless transmission distance. What we study in this paper is the short-distance loss preventer, 2.4GHz wireless technology. It is a global frequency band. The developed products have global versatility, and all kinds of wireless products can use this frequency band. At present, it is widely used in wireless construction, wireless broadband router and other indoor occasions. It is a short-range wireless transmission technology. Now there are many standard wireless protocols in the 2.4GHz frequency band. They have a long transmission distance and strong anti-interference. Therefore, we need to ensure that there is enough anti-interference and data continuity in the 2.4GH frequency band.<br>NRF24L01 can build wireless network conveniently because of ant protocol. Ant's wireless personal LAN communication technology keeps the integrity of data, and has the advantages of low consumption and low cost. NRF24L01 is a FSK modulated wireless communication chip, which can communicate point-to-point and 1-to-N at high speed. MCU only needs to provide 5 common pins and one interrupt pin for nRF24L01 wireless module to realize the communication function. So it is very simple for MCU system to build wireless communication function and use nRF24L01.<br>