Common wireless transmission technology in mobile phones | Aiguo Mobile - 上海419贵族宝贝-上海后花园1314-上海品茶网-阿拉爱上海

Now the mobile phone market is very competitive, accompanied by a series of new technological innovations, including wireless transmission technology. The traditional infrared transmission technology has been replaced by Bluetooth, and the single Bluetooth technology is slowly being replaced by the combined technology of NFC.

infra-red

In fact, the function of infrared transmission is rare in smart phones nowadays, but in the era of functional phones before, infrared technology was still very common. I remember that when I was in high school, a group of roommates used the infrared function of the Nokia 8250 when playing Snake on the computer. Snake is definitely out now, but it was very popular when there were not many games to choose from. However, it is quite troublesome to play with computers. The main reason is that the transmitters must be aligned with each other in the process of infrared transmission. A slight deviation will cause disconnection. In addition to playing games online, another function of infrared was to transmit ringtones and pictures.

Since the speed of ordinary infrared is 115.2kbit/s, and that of fast infrared is only 4Mbps/s, this speed can no longer meet the needs of most people. In addition, transmitters must be aligned with each other during data transmission, so this technology is quite inconvenient compared with Bluetooth, so it has been basically eliminated in current smart phones.

Bluetooth

I believe everyone is very familiar with the function of Bluetooth. Now almost every smartphone will be equipped with Bluetooth. We often use Bluetooth headsets to transmit pictures through Bluetooth.

One of the characteristics of Bluetooth is low power consumption, but the transmission speed is average. The transmission speed of Bluetooth 4.0 is only 24Mbp/s. In addition, Bluetooth transmission also requires a pairing process. In many cases, you will find that the pairing time is much longer than the time for you to transfer pictures.

WiFi Direct

WiFi Direct, also known as WiFi point-to-point, enables data transmission between devices without the need for wireless routers. That is to say, even if there is no wireless network in the outdoor environment, using the Wi Fi Dircet function can enable two devices to connect through Wi Fi, which is also very advantageous in the connection distance. It can even enable mobile devices to keep connected within 100 meters. The speed is even more amazing. The theoretical transmission rate can reach 250Mbps, or 31MB/s. Although the theoretical speed is quite different from the actual speed, there is basically no problem in transmitting 1GB files in three minutes.

NFC

NFC (Near Field Communication), a Chinese name for near-field communication technology, was first developed by Philips and Sony. It is a short-range high-frequency wireless communication technology that enables two devices to carry out point-to-point data transmission. NFC provides a simple, intuitive and fast way to share files. And the sharing operation is also very interesting, as long as two phones are back-to-back.

Since the transmission distance of NFC is only a few centimeters, and it is a point-to-point mode, the NFC transmission process is quite secure and highly confidential. In addition, NFC has a very important advantage that its connection establishment time is very short, less than 0.1 seconds, and it can basically achieve touch and transmit, while the pairing time of Bluetooth is at least 5 seconds.

However, compared with other transmission modes, the transmission speed of NFC can be said to be tortoise speed. The transmission speed of NFC is only 424kbit/s. Therefore, NFC is only suitable for transmitting small data such as business cards and website links.

Android Beam and S Beam

Although the transmission speed of Bluetooth and WiFi Direct is much faster than NFC, the pairing time of Bluetooth and WiFi Direct connection are time-consuming and troublesome. Therefore, someone came up with the idea of using NFC for pairing, and then transmitting via wifi or Bluetooth, which can achieve fast pairing and connection, and also achieve a higher transmission speed. Now we can see that Android Beams rely on NFC for pairing and then use Bluetooth for transmission. In addition, Samsung has similar functions, which use NFC for pairing and WiFi Direct for transmission.

However, both Android Beam and S Beam must be supported by NFC. However, few mobile phones are equipped with NFC. So up to now, Android Beam and S Beam, two better transmission methods, have not been well popularized. The true popularization of NFC must be promoted by a powerful company.