Car antenna(2)

 

Car antenna and antenna, general car aerial for car radio and radio, can be divided into motor vehicle built-in antenna and external antenna. But according to different uses car also has mounted the other antenna. As the bus has DVB-T antenna, car TV antenna. Logistics and taxi is also equipped with GSM, GPS antenna satellite antenna. Radio and radio antenna is mainly AM / FM antenna, soft PCB digital antenna, AM / FM / TV antenna. According to different functions and purposes, the antenna frequency is also different.
Structural classification
Vehicle mounted antenna structure is shortened, the 1/4 wavelength, central loading type, 5/8 wavelength, 1/2 double wavelength antenna in the form, theory on their efficiency increased, the same band antenna length also increases.
Shortened type
As the vehicle itself is limited, plus a long antenna in the vehicle travels at high speed is formed when the wind hole, bridge, entering the underground garage is a problem, so the vehicle antenna and is not longer, general requirements of car antenna not exceeding 70 cm, shorter van-like antenna. Shortened type antenna has the advantages of small volume, although the gain is not high, but is suitable for use in need of concealed antenna.
The 5/8 wavelength and central loading type
The general police vehicle proposals to install Gao Zeng antenna, especially in the active area of relatively large vehicles, 350MHZ high gain antenna much divided into 5/8 wavelength wave form, from the antenna on top of a 1/2 wavelength range with a loading coil. 400MHZ band dual 1/2 wavelength antenna with high gain, the exterior features are antenna vibrator has two loading coil. The 5/8 wavelength and central loading type also has higher gain, and the price is cheaper, so it has been widely used. In as a temporary fixed station antenna used on occasion can consider using high gain antenna, antenna length will not have too much limitation. Because the antenna is designed according to car use in as fixed when in use, the suction of a radius greater than 1 meters of sheet metal ( such as tin ) will have better use effect. Because the original imported vehicle antenna is very expensive and the advantage is not prominent, so generally choose homebred car antenna. In the antenna selection phase reference antenna shape and gain. Suggested the use of major manufacturers of brand-name products, they provide the parameters of authenticity is relatively high, production process is guaranteed. If the bulk purchase can be to the professional manufacturers to use frequency band antenna custom, to obtain the optimal use effect.
Frequency division
The GSM antenna
Operating frequency: 1 900MHZ / 1800MHZ 900MHZ: 3dBi 1800MHZ: 3dBi gain gain
2 VSWR: GSM ' 1.8 DCS ' 1.8
3 line: RG174 line, 3 meters / 5 feet
4 installation methods: magnetic adsorption
Application of joint SMA / SMB: 5 / GT5 / BNC / MCX / MMCX
6 working temperature: - 20 DEG C to + 85 C
The 7 storage temperature: - 40 DEG C to + 90 C
The TV antenna
The 1 power supply voltage DC 10.5 ~ 16.5V
60 ~ 100MA 2 power supply
48 ~ 860MHZ 3 work frequency
The 4 gain 15 + 3DB
5 noise coefficient is equal or less than 7DB
6 output impedance 75 ohm
The 7 output VSWR < 3
8 environmental temperatures of - 20 degrees C ~ + 70 C
The 9 storage temperatures of - 40 degrees C ~ + 90 C
Radio antenna
The 1 power supply voltage DC 10.5V ~ 16.5V
2 supply current < 80 MA
The 3 work frequency of AM / FM /
The 4 amplifier gain AM 5 + 3dB FM 3 + 3dB
5 output impedance 75 ohm
The 6 antenna angle 65 degrees
7 environmental temperatures of - 20 degrees C ~ + 85 C
The 8 storage temperatures of - 40 degrees C ~ + 90 C
Functional classification
Car antenna
A small car antenna, along with a digital radio, mobile TV, GPS navigation and language recognition and other functions, declared 10 national invention patents. For receiving and strengthen the radio signal, the current signal in most regions of China is very weak, the car also required an external antenna, the signal instability in the region has a great help. Car antenna is an electrostatic releaser, is mainly a running vehicle shell build-up of static electricity release, protecting the safety of passengers and car circuit. Car antenna refers to the design and installation on the vehicle mobile communication antenna, the most common is the sucker antenna. Because the antenna installation are easy, so in some simple table occasions often used instead of base antenna antenna. Take good care of. By type: 1, car TV antenna 2 antenna 3, car radio, car GPS antenna 4, car 5, anti-static antenna automatic telescopic antenna in installation type: 1, type 2, type 3 paste, plug in type 4, 5, 6, top thread suction glass 7, card edge type