The development history of wireless mice

Original title: "How does a wireless mouse become wireless?" 》

Wireless mice have gradually become a standard feature of today’s office computers. From now on, we no longer have to drag long cords around. But, how does a wireless mouse work? Today we will learn together

No.1 The development history of wireless mouse

Did you know that the wireless mouse is now 40 years old? In 1984, Logitech developed The world's first wireless mouse, but this wireless mouse used infrared rays as a signal carrier. It was said to look like the picture below, but it later failed due to performance reasons. It wasn’t until ten years later in 1994 that Logitech finally successfully developed a wireless mouse that worked at 27MHz. This 27MHz frequency also became the working frequency of wireless mice and keyboards for a long time. Known as 27MHz technology. In 1998, the SIG Alliance was established, Bluetooth technology came out, and wireless mice based on Bluetooth technology began to be successfully developed and commercialized. Up to now, wireless mice have mainly used wireless communication methods, including Bluetooth, Wi-Fi (IEEE 802.11), Infrared (IrDA), ZigBee (IEEE 802.15.4) and other wireless technology standards.

No.2 Technical Solution for Wireless Mouse

2.1, 27MHz TechnologyAs mentioned above, Logitech developed the first wireless mouse working at 27MHz in 1994, and later also It has slowly developed into a wireless communication technology based on the 27MHz ISM frequency band, with output power requirements less than There are four global channels in this frequency band: two of them are used for wireless keyboards , and the other two are for wireless mice; the working frequency of the wireless keyboard is 27.095MHz and/or 27.195MHz, and the working frequency of the wireless mouse is 27.045MHz and/or 27.145Mhz. In this way, the wireless mouse and wireless keyboard will not easily interfere with each other when working. However, the communication distance of this wireless technology is short, the effective transmission distance is only 182cm, less than two meters, and it only supports single transmission, the power consumption is relatively large, and the security is low. The picture below is a wireless mouse launched by Microsoft based on 27MHz ISM communication technology. The other one with a long line is the wireless mouse receiver. 2.2 2.4G / 5.8G wireless technologyAt present, most wireless mice work in these two frequency bands. 2.4G and 5.8G are also standard ISM frequency bands. 2.4G wireless technology The operating frequency is from 2.4GHz to 2.4835GHz; 5.8G wireless technology includes three 5GHz frequency bands, frequency band 1 is 5.15~5.25GHz, and its EIRP is stipulated not to be greater than 23dBm and is suitable for indoor wireless communications; frequency band 2 is 5.25~5.35GHz, stipulated Its EIRP is no more than 30dBm and is suitable for medium-distance communications; frequency band 3 is 5.725~5.825GHz. Usually people choose 5.725~5.825GHz for community broadband wireless access to obtain better performance-price ratio. The application of 2.4G wireless technology has better solved the problems of power consumption and transmission distance of 27MHz wireless technology. The 2.4G transmission efficiency has reached 2Mbps, which is much higher than the 27Mhz transmission efficiency. There is no need to work continuously for a long time, the problem of high power consumption of the product has been significantly improved, and the battery life has been greatly improved. Different from 27MHz, 2.4G uses automatic frequency modulation technology, the receiver can automatically find the available frequency band, and the mutual interference of 27Mhz products has been well solved. 2.4GHz wireless technology supports two-way transmission mode, and the signal intermittent situation that occurs in 27Mhz one-way transmission is also effectively improved. Not only that, the data transmission speed of 2.4GHz wireless technology is also faster than 27MHz. Currently, many manufacturers based on this wireless technology have launched "zero delay" products, which not only meet the needs of the majority of users, It is also an excellent product for some demanding gamers. The picture below is the zero-latency G7750 2.4GHz wireless mouse launched by Shuangfeiyan2.3 Bluetooth technology We will take you to understand the past and present of Bluetooth in this article! "The characteristics and advantages of Bluetooth technology are introduced in detail. Bluetooth works in the ISM frequency band we are most familiar with, which is 2.4GHz, with a bandwidth of 83.5MHz, from 2.4GHz-2.4835GHz, and shares this frequency band with our commonly used wifi. So how to deal with the interference between them? Bluetooth uses frequency-hopping spread spectrum technology FHSS (Frequency-Hopping Spectrum Spred). This technology divides the frequency band into 79 frequency modulation channels with 1MHz intervals. The signal of the Bluetooth device jumps from one channel to another in a pseudo-random manner, from the surface See, Bluetooth occupies the entire ISM band, but only about 1MHz of the band is actually occupied, and the frequency modulation rate is 1600 hops per second. At the same time, in order to avoid potential interference, the standards organization proposed the wireless personal area network standard IEEE802.15 based on the Bluetooth protocol to solve the coexistence problem between Bluetooth and wireless network Wifi. Up to now, Bluetooth technology has been updated to the fifth generation, and its communication speed and communication distance have been significantly improved compared to the previous generation. The picture below shows the Professor 1 wireless Bluetooth mouse launched by HP, which supports three connection modes: 2.4G wireless, Bluetooth and wired. In addition, there are infrared mouse, optical mouse, and laser mouse. The comparison chart of different technologies is as follows##No.3 Circuit design of wireless mouse

We found some wireless mouse circuit design models. The following figure shows the hardware design and software design diagram of the wireless mouse for your reference and learning

3.1 Hardware block diagram and software block diagramHardware architecture diagram of wireless mouse

Software architecture diagram of wireless mouse

Logitech wireless mouse circuit schematic diagram

3.2 PCB and structure diagram of the wireless mouseFor a clearer view, there is also a transparent mouse, which can be directly used without disassembly You can see the circuit board structure inside. This article comes from the WeChat public account: Radio Frequency Academy (ID: RF_Center), author: iRFer

The above is the detailed content of The development history of wireless mice. For more information, please follow other related articles on the PHP Chinese website!