Industrial-grade 4G router TCP/IP network architecture 1. Layering of TCP/IP network system   TCP/IP (TransmissionControlProtocol/InternetProtocol), transmission control protocol/Internet protocol. It was developed by the defense advanced research projects agency in the 1970s, and was later integrated into UNIX and popularized. It emerged in the 1980s as the Internet's...


The structure of 4G DTU The main function of DTU is to transmit data from remote devices back to the background center via wired/wireless. Different data transmission modes of DTU include all-network-connected DTU, GPRS DTU, WIFI DTU, CAN DTU and 4G DTU. Today, we will have a look at the structure and work flow of DTU.   To complete...


What are the wireless connection technologies of the... Internet of things (iot) applications have been deeply rooted in our lives. The E-Lins H685 industrial-grade router is a small industrial-grade wireless router with single or double LAN ports. TDD/ fdd-lte, 4G, 3G, GPRS network optional. Besides, what are the wireless connectivity technologies for the Internet of things?   1....


The use of industrial wireless routers Industrial-grade wireless router adopts high performance 32-bit industrial-grade ARM9 communication processor, which is widely used in finance, electric power, postal, water conservancy, environmental protection, meteorology and other industries.   Industrial router is mainly used in intelligent transportation,...


Cascade and stack of industrial-grade 4G routers The most basic star Ethernet architecture, the actual star enterprise network may be much more complex than this. This renaturation is not only reflected in how high-end network equipment, how complex configuration, more importantly, the performance of network switching level is more complex. Industrial routers and firewalls...



Antenna Gain

文章目录 : 其他

For a better understanding about antenna gain, you can go through this article.

Antenna gain is often quoted with respect to a hypothetical antenna that radiates equally in all directions, an isotropic radiator. This gain, when measured in decibels, is called dBi. Conservation of energy dictates that high gain antennas must have narrow beams. For example, if a high gain antenna makes a 1 watt transmitter look like a 100 watt transmitter, then the beam can cover at most 1/100 of the sky (otherwise the total amount of energy radiated in all directions would sum to more than the transmitter power, which is not possible). In turn this implies that high-gain antennas must be physically large, since according to the diffraction limit, the narrower the beam desired, the larger the antenna must be (measured in wavelengths).

Antenna gain can also be measured in dBd, which is gain in Decibels compared to the maximum intensity direction of a half wave dipole. In the case of Yagi type aerials this more or less equates to the gain one would expect from the aerial under test minus all its directors and reflector. It is important not to confuse dBi and dBd; the two differ by 2.15 dB, with the dBi figure being higher, since a dipole has 2.15 db of gain with respect to an isotropic antenna.

Gain is also dependent on the number of elements and the tuning of those elements. Antennas can be tuned to be resonant over a wider spread of frequencies but, all other things being equal, this will mean the gain of the aerial is lower than one tuned for a single frequency or a group of frequencies. For example, in the case of wideband TV antennas the fall off in gain is particularly large at the bottom of the TV transmitting band. In the UK this bottom third of the TV band is known as group A, see gain graph comparing grouped aerials to a wideband aerial of the same size/model.

Other factors may also affect gain such as aperture (the area the antenna collects signal from, almost entirely related to the size of the antenna but for small antennas can be increased by adding a ferrite rod), and efficiency (again, affected by size, but also resistivity of the materials used and impedance matching). These factors are easy to improve without adjusting other features of the antennas or coincidentally improved by the same factors that increase directivity, and so are typically not emphasized.

E-Lins router has stardard 3dbi cellular antenna. This is enough for normal use. If you want to put it in rural place or place with bad reception, it’s better to get a high gain antenna.


You must be logged in to post a comment.