Today, we talk about the comparison of 433 MHz and 2.4 GHz wireless communication, the 433 MHz vs 2.4 GHz wireless communication technology.
433 MHz vs 2.4 GHz wireless technologies, each of them has its own characteristics, which one should I choose?
Both 433 MHz and 2.4 GHz wireless technologies belong to short-range wireless communication technologies, and both use ISM license-free frequency bands, but they have their own characteristics.
2.4GHz advantages in 433 MHz vs 2.4 GHz
Normal upgrade of 2.4GHz technology in 433 MHz vs 2.4 GHz
The long-term stability and reliability of the system work are the most important indicators of a wireless communication system.
Since the general 433MHz and 915MHz products use low-frequency narrowband communication technology, their working frequency range is very narrow 5-25 kHz, and the working frequency points of the two wireless transceivers must work within this very narrow frequency range.
They can communicate with each other, otherwise, they cannot communicate with each other.
Due to the crystal oscillator’s oscillating frequency, temperature drift, and aging over time, errors will cause the working frequency to drift, so that the working frequency of the two wireless transceivers cannot fall on this very narrow working frequency band, resulting in the system Unstable, and finally unable to communicate at all.
In order to solve this problem, military low-frequency narrow-band communication systems often need to use a constant temperature device (constant temperature bath) to reduce the influence of crystal temperature drift, but this will inevitably increase the cost.
Although there are some other technologies that can help reduce this impact, they are limited. Therefore, existing new wireless communication systems often use broadband spread spectrum technology, and wireless transceiver systems that use general narrowband communication technology may not show up in temporary trials and short-term use, and long-term use will be unstable.
Technical performance of 433 MHz vs 2.4 GHz, micropower, and direct sequence spread spectrum schemes:
(1) 433 MHz trillion is an old product in the field of data transmission, and it has huge hidden dangers when used for data transmission:
The 433 MHz system, its fatal weakness is that system has poor security and confidentiality, which is easy to be attacked and deciphered;
The communication technology is backward, and the system communication technology uses the backward narrowband amplitude modulation technology, generally 5-25Khz; it uses a single frequency point to work, which can not effectively resist the multipath effect caused by occlusion, resulting in unreliable communication and unstable system;
The channel is very crowded, and the environmental interference is extremely large. Walkie-talkies, vehicle-mounted communication equipment, amateur communication equipment, etc., are all concentrated here, so the environmental interference is very large;
The problem of frequency drift is serious, and it can’t be found in a loose test. It may not be seen in short-term use, but it will inevitably appear in long-term use;
In addition, the power consumption is large, the transmitter and antenna are bulky, and the large-scale use will affect the health of personnel. Interference with a large number of other 433 MHz communication products in use will cause social repercussions.
At present, China has no ready-made RFID frequencies in the UHF band that can be directly planned. Therefore, when we consider the RFID planning of this band, we must carefully consider the issue of frequency sharing with existing radio equipment.
(2) 2. 4 GHz is a contemporary advanced data transmission system and an independent innovation of wireless data transmission.
4G wireless communication
The 4G solution belongs to a microwave, micro-power, broadband, and direct-sequence spread spectrum peer-to-peer communication system. The system has the following main features:
Micropower
The transmission power is 100 milliwatts (0.1 watts), which is an energy-saving and environmentally friendly product, which is in full compliance with the notice of the Ministry of Information Industry on adjusting the 2.4GHz frequency band transmission power limit and related issues (the Ministry of Information does not have document No. [2002] 353) the regulations are free frequency bands;
2.4GHz ISM band in 433 MHz vs 2.4 GHz
The 2.4 GHz frequency band is an internationally-used free frequency band. This frequency band is also called the ISM band. It does not refer to a frequency point but refers to the entire frequency range from 2400 megabytes to 2483.5 megabytes, a total of 83.5 megabytes of bandwidth.
It can allow multiple different channels of multiple different communication systems to be used together. The main communication systems allocated in this frequency band are Bluetooth (Bluetooth), broadband local area network (WIFI), wireless data transmission network (Zigbee), and other communication systems.
In order to avoid possible mutual interference between the relevant departments when carrying out this kind of frequency allocation, they have considered the different ways of working between them.
At the same time, the maximum use power of these communication systems is limited, and the influence of their wireless signals is limited to a very limited distance range.
For example, in the office or home area, through frequency division and code division technology, 100 2.4 GHz public systems can work in this frequency band without interfering with each other;
Adopt advanced direct sequence spread spectrum technology
Direct sequence spread spectrum technology comes from military communications. Super anti-interference ability, extremely high working reliability, and confidentiality are the basic requirements of military communications. Industrial automation control systems often have similar requirements, which is also direct sequence expansion.
The main reason for the introduction of frequency technology into the industrial control field. Compared with the existing general wireless communication methods, the direct sequence spread spectrum communication method has the following obvious advantages:
1) Good anti-interference performance:
It can coexist with the narrowband of the same frequency band without affecting its normal operation;
2) Strong ability to resist multipath fading:
Multipath fading is a prominent problem that affects the quality of mobile communications. It is usually necessary to adopt technologies such as space diversity and adaptive equalization to overcome it, and there is a large fading margin.
Direct sequence spread spectrum technology can use multipath signals to provide path diversity, which not only eases Rayleigh fading but also eases slow fading caused by physical obstruction, thereby greatly improving communication quality;
3) Compared with general non-direct sequence spread spectrum communication technology, direct sequence spread spectrum communication technology has much lower requirements on environmental noise:
In the same noisy environment, when non-direct sequence spread spectrum communication equipment can no longer communicate normally, the equipment using direct sequence spread spectrum communication technology can still work very well.
The CDMA signal-to-noise ratio using direct sequence spread spectrum communication technology is 3.7 times that of DAMPS and TDMA, 11.2 times that of TACS, 13.6 times that of AMPS, and 20 times that of FM/FDMA;
4) Good communication quality:
The CDMA system adopts direct sequence spread spectrum technology and comprehensively applies multiple diversity technologies such as time diversity, frequency diversity, space diversity, and path diversity to overcome multipath effects and obtain strong anti-interference capabilities.
The direct-sequence spread spectrum communication system is broadband and low-noise ratio, and the waveform allows the use of high-redundancy error correction coding and high-efficiency digital modulation technology to ensure high-quality data transmission;
5) Highly reliable confidential security:
The direct sequence spread spectrum technology comes from military communications. The communication system using direct sequence spread spectrum technology is a secure communication system. If a certain encryption algorithm technology is added, the communication security performance can be greatly improved, which is unmatched by FDMA and TDMA systems Analyzing the spread spectrum system it uses, it is almost impossible to intercept other people’s communication content.
It can also easily set and change the master key, secondary key, spread spectrum code table, standard encryption algorithm, etc. in the system, making communication confidentiality more reliable.
Each communication method has its own characteristics and advantages. When we adopt it, we must decide whether to use the 433MHz or 2.4GHz frequency band according to the characteristics of the terminal product.
If you have any 433 MHz vs 2.4 GHz antenna questions, please read our ANTENNA FAQ section, if you still cannot get the answer you need, please contact us.
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