Using radio frequency technology products are used radio waves to transmit control signals, and its directional characteristics, can not "face to face" control, distance, up to tens of meters. Between the transmitter and the receiver can play as long as there is no shielding effect of the metal barrier material, can be used normally. RF technology, product cost is usually higher, but no direction, more convenient, more so by the users. Promise as a wireless presenter series, most are used in radio frequency technology. green laster pointerwith remote control is composed of a emitter, a receiver and a USB port. 2.4GHz RF technology is referred to a working band, 2.4GHz ISM (Industry Science Medicine) is the world's open free wireless band. Work in the 2.4GHz band can get a stronger anti-interference ability, and because transmission power is small, more suitable for battery-powered products. 315MHZ and 433MHZ is our country free of transmitting and receiving frequency of application for long-distance transmission, diffraction ability. This product is used in the field of wireless meter reading than the more launch power, energy consumption is relatively large, is not suitable for battery-powered applications. 19.2.4G the promise of wireless presenter products, and other manufacturers of 433M, 315M of product compared to what advantage? The USB port is also a part ofgreen laster pointer. 2.4G Wireless Presenter of promise for the product, the use of the international brands of chips, the use of more advanced and mature technology. On the performance of the product is the wireless transmission more stable, anti-interference ability. At the same time as the maximum transmit power chip is 0db, 1mw, so the relatively low power consumption, battery life is relatively strong. In addition, 2.4G products, wave length, the diffraction is poor, not suitable for long-distance transmission. If you want to use the 2.4G technology in 1mw power under 20 meters, 30 meters, the antenna requires more sophisticated debugging, usually requires a special radio frequency engineer to do, and this part is most of the manufacturers of the short board. 433M, 315M of products, longer wavelength, the diffraction ability, suitable for long-distance transmission, in the long-distance remote control, remote control cars children, a large field of wireless operating table use. The infrared technology ofGreen laser pointeris not that usually used. Most of these RF chip technology used are relatively simple, not complex modulation and error correction, the chip price is cheaper. Commissioning of the antenna, the demand is not high. Some manufacturers do not even have a special radio frequency chips, take a simple RF circuits, using half-duplex mode of work, but also to achieve remote control. However, this simple circuit, there is no way to transmit power control, and battery power when the long distance remote control, remote voltage drop after a short distance. At the same time there are not any anti-jamming capability. At present, most manufacturers are willing to do 433M of product, technology is easy, the cost is relatively low. But there is anti-interference ability, the general problem of excessive battery consumption. The radio frequency technology ofgreen laster pointeris commonly used in the market. Can. A transmitter can simultaneously control multiple receivers, but all need to re-yard receivers. Promise as a wireless presenter products, each presentation can also be called the transmitter, the factory has a unique address code. This address is the factory when the code is burned inside the chip is fixed, can not be changed. Wireless Presenter receiver has an internal memory, the receiver in the state of the code, you can receive the address code stored in memory, we called it "code." Receivers and transmitters on the code after the formation of a one to one relationship, only to receive the control signal transmitter. 2.4G technology of关键词is also used.