As one of the common electronic devices in our daily life, earphones are deeply loved by people. There are Wireless Bluetooth Headset, Wireless Earbud , Headband Headphones, Computer Headphones, Wooden Headphones, Noise Cancelling Headphones, Airline Headphones, Mobile Phone Earphones, Bluetooth Neckband Headphones, Sport Earphone ...
In recent years, with the continuous improvement of people's living standards, various portable devices in life have been increasing, and people are often entangled by various wires, causing certain inconvenience to life and work. In order to make the use of earphone products more convenient, major companies have developed wireless headsets. The signal transmission has experienced the evolution of FM, infrared, 2.4G technology, Bluetooth, kleer and other technologies. Each generation of technology is constantly improving the transmission bandwidth and speed. As well as hearing quality, it also reduces the cost of high quality audiovisual equipment. The following is a brief introduction to the current development of wireless headsets.
FM Wireless Headset
F M is an abbreviation for English frequency modulation, referred to as FM. The wireless earphone with FM technology appears earlier. The principle is to transmit the audio signal through the FM transmitter, and install the FM receiving circuit in the earphone, which can both listen to the unique signal source and listen to the FM radio. Headphones. Since FM FM technology was originally used for radio station broadcasting, it is suitable for long-distance, large-area reception, but its sampling rate of up to 22 kHz is called "radio sound quality", so FM wireless headphones have poor sound quality and confidentiality. Strong and susceptible to interference. Also because FM technology is mainly used for one-way transmission, FM wireless headphones cannot integrate wireless microphones. The above characteristics make FM wireless technology usually used in low-end earphone products. Its price is very low. It is widely used in foreign language listening training, foreign language listening test and simultaneous translation. There are many domestic FM wireless earphone brands available on the market. For: RMB50-500 yuan.
Victory FM Wireless Headset UHF-948FM
Infrared Wireless Headphones
Infrared is a light wave. Except for strong light, there are few transmissions that can affect infrared wireless. Therefore, it has good stability and is widely used in various remote controllers, wireless mice and early mobile phones. The biggest advantage of infrared wireless technology is bandwidth, which means that audio products using infrared wireless technology can transmit large-capacity signals with good sound quality.
SONY's MDR-IF240RK headphones use infrared wireless transmission technology (see Figure 2). You don't have to worry about affecting your family when you watch TV. The transmission distance is up to 7m. Even if you walk around the room, you don't have to worry about the signal range. This headset uses a 30mm diameter drive unit, which allows the listener to feel the shocking low-frequency effect, watching TV, movies or sports competitions in the dead of night, all have good results.
SONY infrared wireless headset MDR-IF240RK
However, the shortcomings of infrared wireless technology are also obvious. Firstly, it has extremely high requirements on directivity. It is easy to receive signals because the angle is slightly deviated. Secondly, the infrared transmission distance is short, the effective distance is usually less than 10m, and infrared wireless transmission is for transmitting. The power requirement is higher, so the power consumption is large. If you need to replace the battery or charge frequently, it is contrary to the convenience of the wireless headset.
2.4GHz wireless headset 2.4GHz wireless technology headset uses 2.4GHz band wireless carrier technology and P2P communication protocol. From the aspect of transmission rate, in theory, the audio transmission rate of "CD-level sound quality" needs to reach about 1.4Mh/s, and the current 2.4GHz wireless transmission method using P2P protocol can reach 2Mh/s, so it can basically reach Non-destructive transmission requirements, as well as the ability to integrate wireless microphones for two-way operation.
Audio-Technica has a nice 2.4GJHz digital wireless headset - the ATH-DWL5000.
Audio-Technica Wireless Headset ATH-DWL5000
The machine adopts a 53mm diameter unit, which can completely cover the ear when worn, and the space in the auricle is very good. The signal receiving effective distance is about 30m. It should be noted that the ATH-DWL5000 has two modes of A/B. In the A mode, one earphone is used for one transmitter, and 24it digital signals can be sent. In the B mode, multiple headphones are received at the same time. For multi-person use, only 16hit digital signals can be transmitted. ATH-DWL5000 has 5.1 analog multi-channel effect, the positioning is very good, the reference price is: RMB5000.
Audio-Technica Wireless Headset ATH-DWL5000 Transmitter
SONY also has a very cost-effective 7.1-channel wireless headset - MDR-DS7100. This headset uses 2.4GHz wireless technology, 50mm size pronunciation unit, the sound quality is excellent. With the SONY "VirtualphonesTechnology" virtual surround sound technology, the surround effect of the headphones is significantly improved. Support MPEG2AAC, DolbyDigital, DTS, DTS-ES, DolbyNRprofessionallogicllx, designed with a special game mode, with real-time channel selection to avoid interference from radio waves and other devices. The reference price is: RMB2100.
SONY Wireless Headset MDR-DS7100
The 2.4 GHz technology wireless headset itself has low power consumption and relatively low power consumption. By increasing the power of the transmitter, the transmission distance can also be effectively increased. With the popularity of computer networks and the development of video calls, the application field of 2.4GHz wireless headphones can be described as quite extensive, and the market prospect is promising.
