What wireless communication products does Shanghai Luoxun have?

Henan Xunluo Communication-walkie-talkie signals in common ditches, tunnels, star-rated hotels, Grade A office buildings, urban complexes, bank buildings, high-grade houses, government projects, museums, gymnasiums, large exhibition centers, universities, large hospitals, airports, railway stations, subways, large factories, industrial parks, large shopping malls, etc. are enhanced to solve blind spots.

Main brands: Motorola, Jianwu, Hainengda, Vitex, public network walkie-talkie, vehicle-mounted station and relay station. The walkie-talkie is mainly used in large-scale property, railway, aviation, forestry, petroleum, electric power, public security, colleges, water conservancy, prisons, shopping malls, tunnels and other industries, and is used for communication and command and dispatch among group members, so as to improve communication efficiency and quick response ability to emergencies. With the introduction of walkie-talkies into the civilian market, people began to use walkie-talkies more and more when they went out to travel and shop.

Henan Xunluo Communication Technology Co., Ltd. is a high-tech enterprise specializing in providing wireless intercom solutions, mainly providing customers with building wireless intercom, underground common ditch wireless intercom and tunnel wireless communication systems; We can not only provide customers with complete sets of wireless intercom products, but also provide all-round services such as customized solutions and technical training according to the project.

Communication has been committed to providing customers with high-quality wireless intercom solutions, and has accumulated different mature wireless intercom solutions for customers in different industries. Including wireless intercom, telephone interconnection, IP interconnection, trunking system, etc.

Tel: 037 1-86 132233.

1 What is the "distance" of the walkie-talkie?

After various industries and commercial users, walkie-talkies have become the first choice for many ordinary consumers in recent years. No matter in road trip or outdoor mountain climbing or hiking, walkie-talkies are becoming more and more popular among ordinary users, because they can talk quickly without relying on the mobile phone network. But for most people who come into contact with walkie-talkies for the first time, the first question they think of is-how far is the transmission range of walkie-talkies?

Get out of the misunderstanding of parameters and the factors affecting the distance of walkie-talkie

Generally speaking, although the transmission distance is indeed an important performance parameter index of walkie-talkies, after all, many people want to know the time of signal transmission and reception between their own equipment and other equipment when they go out to use walkie-talkies. However, there is no concept of "distance" in wireless communication specialty, because the use of ultrashort wave communication will be affected by many factors in different situations.

But for most people who are new to walkie-talkies, only by understanding the factors that will affect the communication distance will they have a clearer understanding and judgment of the concept of "distance" and make purchases. This paper will briefly explain these different factors, hoping to provide some help to people who are new to this product.

Because voice signals are transmitted by radio waves between walkie-talkies, there are many factors that affect the transmission distance of walkie-talkie signals. Including internal parameters and external environmental factors of walkie-talkie. First of all, let's briefly understand which parameters of the walkie-talkie itself will affect the signal transmission distance.

Get out of the misunderstanding of parameters and the factors affecting the distance of walkie-talkie

Digital machines and simulators

One: Signal mode

At present, there are two kinds of walkie-talkies on the market: digital walkie-talkies and analog walkie-talkies. Due to the provisions of document No.666 of the Ministry of Industry and Information Technology, the traditional analog walkie-talkie is no longer produced, so the domestic walkie-talkie industry is currently transitioning from analog to digital. In other words, we can still buy walkie-talkies that use analog signal transmission.

Literally, the biggest difference between analog walkie-talkie and digital walkie-talkie lies in the way of signal transmission. Regardless of other factors, the walkie-talkie with digital signal transmission is superior to the analog walkie-talkie in anti-interference and signal strength, so from this point of view, the transmission distance of the digital walkie-talkie is superior to the analog walkie-talkie.

Get out of the misunderstanding of parameters and the factors affecting the distance of walkie-talkie

The manufacturer will clearly mark the walkie-talkie power.

Two: Power

For radio equipment, transmission power is a very important basic parameter. The difference of power will directly affect the stability of data transmission and the transmission distance of signals. Simply put, without considering the influence of other factors, the signal distance emitted by high-power walkie-talkies is greater than that of low-power walkie-talkies.

Get out of the misunderstanding of parameters and the factors affecting the distance of walkie-talkie

Professional digital walkie-talkie

At present, the walkie-talkies on the market are divided into public walkie-talkies and civil walkie-talkies, and the common transmission power ranges from 0.5W to 5W.. In an ideal state, that is, without any obstacles and interference, the theoretical talking distance of the walkie-talkie with power of about 5W is above 10 km. But in practical use, it is almost difficult to reach this distance.

Therefore, it is misleading for some manufacturers to directly mark the transmission distance of walkie-talkies in the market at present, because manufacturers simply cannot accurately predict the user's use environment.

In addition, the higher the power of the intercom, the better. Excessive power will not only consume more electricity, affect the life of the internal power amplifier components of the walkie-talkie, but also interfere with the communication of other radio waves and even cause radiation pollution. Therefore, the radio management agencies in various countries will have clear regulations on the power of walkie-talkies. China's "Regulations on Radio Management" stipulates that the use of non-public walkie-talkies with power exceeding 0.5W must be applied to the radio management agency in advance, and can only be used after being approved and obtained a radio license.

Three: Internal circuit

The internal circuit mentioned here is the general name of sensitivity, voice processing circuit and anti-interference circuit. For a simple example, when two walkie-talkies with the same power receive a weak signal, the walkie-talkie with strong processing and amplification ability receives a clearer voice. However, ordinary consumers can't directly judge the internal circuit design, so the simplest way is to try to choose the products of those big brands.

Get out of the misunderstanding of parameters and the factors affecting the distance of walkie-talkie

The manufacturer will clearly mark the frequency band range.

Three: frequency band

Common interphone frequency bands are UHF and VHF. UHF is the abbreviation of UHF, which refers to UHF radio waves. UHF refers to the frequency of 300~3000MHz. VHF is the abbreviation of Very High Frequency, that is, very high frequency, which refers to radio waves with frequencies between 30Mhz and 300MHz. In walkie-talkies, the range of UHF frequency band is usually between 400 and 470 MHz, and VHF is between 136- 174MHz. Some professional machines have an even larger frequency range.

Get out of the misunderstanding of parameters and the factors affecting the distance of walkie-talkie

Dual-frequency intercom

Simply put, the biggest difference between the two frequency bands is that UHF band is characterized by poor diffraction and strong ability to penetrate buildings, which is suitable for cities with many tall buildings. Very high frequency (VHF) is characterized by good diffraction and weak ability to penetrate buildings, which is suitable for field and sea operations troops. Simply put, the wavelength characteristics of the two bands are complementary, UHF is suitable for cities and VHF is suitable for open areas.

Therefore, the same walkie-talkie, which frequency band to choose during use will also affect the transmission distance. Only by choosing the right frequency band in the right environment can the use distance be further.

Product: TD500 Hainengda interphone 3 External factors are equally important.

After having a certain understanding of some main internal factors that affect the intercom distance, let's look at those external factors that also affect the signal distance. These factors mainly come from the environmental factors when we use walkie-talkies, including height, obstacles, electromagnetic interference and so on.

One: Height

There is a fashionable saying in amateur radio lovers' circle: "Height is everything". Practice has proved that this is a truth that will never fail. Using walkie-talkies at different heights in the same place, the signal transmission distance is different. Using the characteristics of radio transmission, the higher the place, the farther the signal transmission distance. Someone once held a radio station at the top of Xiangshan Mountain to communicate with people on the high buildings in Tianjin. This is the influence of height on signal transmission distance when using walkie-talkie.

Get out of the misunderstanding of parameters and the factors affecting the distance of walkie-talkie

Buildings will block signal transmission.

Second: Obstacles

Like the height factor, when you use the walkie-talkie, the obstacles in the surrounding environment will directly affect the signal transmission distance. Tall buildings, trees, large vehicles and even outdoor billboards will absorb and hinder radio waves emitted by walkie-talkies. Therefore, buildings and objects that affect signal transmission, such as downtown areas, tunnels and large vehicle parking lots, will affect the transmission distance of walkie-talkies.

Three: environmental interference

The interference mentioned here includes the signal interference caused by other interference sources such as walkie-talkies, wireless equipment and electrical equipment, thus affecting the signal transmission distance. Eliminate the influence of various anti-jamming capabilities inside the walkie-talkie, which is easy to appear in densely populated cities, and different weather, temperature and even day and night differences will also affect signal transmission.

Summary: In fact, there are many factors that affect the signal transmission distance of walkie-talkie, such as antenna type and sensitivity. Due to the limited space, I won't go into details here. I believe that users who have read this article have a new understanding of the concept of "distance", which can be measured according to their actual needs, whether in purchase or use.