As we know,ther handheld barcode terminal can choose 433MHZ or UHF function when purchase.Which one is the more better?
1.the RFID frequency application overview
With the development of society now, science and technology have improved. The application of RFID technology is also becoming more and more widespread, and the frequency allocation problem is getting more and more attention. Since radio frequency identification systems generate and radiate electromagnetic waves, these systems are subtly classified as radios, and radio frequency identification systems cannot interfere or attenuate other radio services while in operation. In particular, it should be ensured that the RFID system does not interfere with nearby wireless electromagnetic waves and mobile radio services.
The choice of operating frequency in the RFID system should also consider the influence of other factors. Can not affect or interfere with other radio services. In our country, we have deliberately reserved a certain frequency range for applications in industries such as industry, science and medical. The use of radio waves is also divided according to the frequency band.
Each frequency also has its own advantages and disadvantages. The transmission distance below 135KHz is about 10 cm short, and the communication speed is slow. This band is open in most countries and does not involve issues such as licensing applications for laws and regulations. Therefore, the scope of use is the widest. Mainly used in pets, access control and anti-theft tracking. The most widely used of these frequency ranges are aeronautical and marine radio services. Timing signal and frequency standard services as well as military radio services. The frequency range of 13.553 to 13.567 MHz is in the middle of the short wave range. According to the propagation characteristics of electromagnetic waves in this frequency band, it is allowed to communicate with black and white. This frequency range is used by different categories of radio services. For example, news and telecommunications services. In China, UHF (Ultra High Frequency) allocated to RFID frequency bands are mainly concentrated in two frequency ranges. One is 840-960MHZ (specifically 840-845MHz and 920-925MHz, the transmission power is 2W), and the other is 433MHZ (the distribution of UHF is different in different countries). The 840-960MHZ frequency band and the 433MHZ frequency band belong to the UHF range, and the advantages and disadvantages between the two are analyzed and compared.
2. the advantages and disadvantages of the 433MHZ frequency
Initially, the frequency range of 430.050 to 440.000 MHz was allocated to amateur radio services worldwide. Some radio enthusiasts use this band for language and data transmission. However, the current range of 433.050 to 434.790 MHz has been largely occupied by various industrial, scientific, and medical (ISM-Industrial-Scientific-Medical) applications. In addition to backscattered RFID systems, there are small telephones, telemetry transmitters, wireless headsets, unregistered short-range wireless walkie-talkies, lock-free access systems, and many other applications that fill this band, each Class card, etc.
433MHZ in the ultra-high frequency (30-1000MHZ) range, the common feature of ultra-high frequency is that it can not be reflected by the ionosphere. The mode of propagation that plays a major role in this band is the spatial wave propagation within the line of sight, as well as tropospheric and ionospheric scattering. The advantage of this band compared to the high frequency band is that small size antennas can be used for low volume systems. Obviously, this feature is particularly suitable for mobile communications. Tropospheric scoping replaces the radio-relay system in some cases because it can be used for hundreds of kilometers without a relay station, and can also have large capacity (multiplexed), which is not possible at low frequencies.
433MHZ is at the low end of UHF. Compared with the high end of 860-960MHZ (usual UHF frequency), it is easy to interfere because the low end can be reflected by the ionosphere. But at the same time, because it is at the low end of UHF, it has the characteristics of some high-frequency electric waves at the same time, the communication is simple, easy to implement, and the cost is low. It is possible to realize long-distance communication with a small power and a much smaller antenna, which is an advantage. These advantages make their applications increasingly widespread. In addition, its UHF communication has high stability, large capacity and strong transmission capability, which makes its advantages more prominent.
3.the advantages and disadvantages of UHF
Since the end of 1997, the frequency range of 868 to 870 MHz has allowed the use of short-range equipment in Europe. Therefore, it can also be used for RFID systems in the 43 member states of the European Postal and Telecom Conference. Some Far East countries are also considering the use of this frequency range for short-range devices. Outside of Europe (US and Australia), frequency ranges from 888 to 889 MHz and 902 to 928 MHz are already available and are used by backscattered RFID systems. At present, the UHF frequency range of China's radio frequency identification system is 860-960 MHz, and the specific regulations are 840-845 MHz and 920-925 MHz.
The radio wave in this frequency range is basically not reflected, the quality of the transmitted information is good, and the stability is high. In radio relay systems, higher frequencies are used, and although the propagation loss increases, high antenna gains can compensate for this loss. Therefore, it is appropriate to use this frequency band, and the capacity can be increased, and more ways can be passed. But at the same time, compared with 433MHZ, the frequency band is relatively complicated and costly, which is the disadvantage.
So when you choose handheld barcode terminal function,please to confirm your using area.
Add: No3 Hao Tai Technology Park,Shenzhou Road 768,Sicence City,Luogang District,Guangzhou,China
No3 Hao Tai Technology Park,Shenzhou Road 768,Sicence City,Luogang District,Guangzhou,China