Standards for dartless measurements

Today we will look at all the current standards IEEE 802.11, which punishes the violation of different methods and speeds of data transmission, modulation methods, transmission intensity, frequencies, what they work on, authentication methods, encryption and much more.

From the very beginning, it has developed so that some standards operate on the physical level, some - on the level of the middle data transmission, and others - on higher levels of the model of interaction between critical systems.

There are the following groups of standards:

IEEE 802.11a, IEEE 802.11b, IEEE 802.11g, IEEE 802.11n and IEEE 802.11ac add the work of edge control (physical process).
IEEE 802.11d, IEEE 802.11e, IEEE 802.11i, IEEE 802.11j, IEEE 802.11h and IEEE standard.
802.11r - middleware parameters, radio channel frequencies, security features, methods of transmitting multimedia data, etc.
IEEE 802.11f IEEE 802.11c - the principle of interaction between access points, the work of radio operators, etc.

IEEE 802.11

Standard IE ЇЇ 802.11 being the “preeminent” among the standards of dartless surveying. Work on him was condemned to death in 1990. As a result, a working group from the IEEE was engaged in this task, which was aimed at creating a single standard for radio equipment operating at a frequency of 2.4 GHz. In this case, the target was to reach speeds of 1 and 2 Mbit/s with the choice of DSSS and FHSS methods.

The work on the creation of the standard was completed in 7 years. Meta bula reached ale shvidkіst. Having secured the new standard, it turned out to be too small for everyday needs. Therefore, a working group at IEEE began developing new, more specific standards.
Developers of the 802.11 standard vouched for the peculiarities of the old-fashioned system architecture.

Why Stilnikovy? It’s really simple: it’s hard to guess that the hulls are widening at different sides to a singing radius. Come out, the calling zone will guess the cell. The skin of this skin operates under the control of the base station, which acts as an access point. Often called a cell basic service area.

So that the basic service areas can be integrated with each other, there is a special distribution system (Distribution System. DS). The lack of a distributed system based on the 802.11 standard makes roaming impossible.

Standard IEEE 802.11 transfers computers without an access point to the robot in a warehouse of one style. And here the functions of the access point are determined by the work stations themselves.

This standard is divided and focused on devices that function in a mixture of frequencies 2400-2483.5 MHz. In this case, the line radius reaches 300 m, without intersecting the topology of the boundary.

IEEE 802.11a

IEEE 802.11a This is one of the promising standards for drone-free surveillance, which covers work in two radio bands - 2.4 and 5 GHz. The OFDM method that is being used allows reaching a maximum data transmission speed of 54 Mbt/s. In addition, transmission specifications and other fluids:

obov'yazkovi 6. 12 n 24 Mbt/s;
Neob'yazkovi – 9, 18.3G. 18 and 54 Mbnt/s.

This standard also has its advantages and disadvantages. The advantages can be considered as follows:

parallel transmission network;
high transmission speed;
Possibility of connecting a large number of computers

The shortcomings of the IEEE 802.1 1a standard are:

smaller coverage radius in the 5 GHz frequency range (approximately 100 m): J the intensity of radio transmissions is high;
Greater quality of ownership compared to other standards;
For the 5 GHz frequency range, a special separate unit is required.

To achieve high data transmission rates, the IEEE 802.1 1a standard uses quadrature amplitude modulation QAM technology in its robot.

IEEE 802.11b

Working above the standard IEEE 802 11b(also called IFEE 802.11 High rate, high throughput) was completed in 1999, and the name Wi-Fi (Wireless Fidelity, drone-free accuracy) is also associated with it.

This standard is based on the Direct Spread Spectrum (DSSS) method using multiple eight-bit Walsh sequences. In this case, the data is encoded using a different sequence of additional codes (SSK). This allows you to reach a transmission speed of 11 Mbit/s.

As a basic standard, IEEE 802.11b operates based on frequency 2.4 GHz, Vikorists have no more than three channels so that they do not overlap. The radius of this boundary becomes approximately 300 m.

The same special standard with the standard є those, with a non -chute (in the way, at the pogirhenny a signal, great widen, the access points. Riznikh Pereshkod) Shvidkiya Dannya can be Zmenshevat to 1 MBNT/s. However, having detected that the signal brightness has deteriorated, the moderation automatically increases the transmission speed to maximum. This mechanism is called dynamic fluid coupling.

Compliant with the IEEE 802.11b standard. possession often clashed IEEE 802.11b*. The variability between these standards affects the speed of data transmission. You can now install 22 Mbit/s using the dual packet packet coding (P8CC) method.

IEEE 802.11d

Standard IEEE 802.11d indicates the parameters of physical channels and edge equipment. This indicates the rules that govern the permissible intensity of transmission in the frequency ranges permitted by law.

This standard is very important, and the fragments for the work of edge control are victorious. The stench does not correspond to the specified parameters. This may cause damage to other devices. operating in a similar frequency range.

IEEE 802.11e

The fragments of the network can be transmitted in different formats and importance, owing to the need for a mechanism that can recognize their importance and give the necessary priority. For this price the standard IEEE 802.11e, Distribution of the method of transmitting streaming video or audio data with guaranteed bandwidth and delivery.

IEEE 802.11f

Standard IEEE 802.11f divisions from the cell to ensure authentication of the boundary equipment (workstation) when the operator's computer is moved from the access point to another, then between the segments of the boundary. In this case, the protocol for exchanging service information is important IAPP (Inter-Access Point Protocol), which is necessary for the transfer of data between access points, which allows for the effective organization of work between divisions of drone-free monitoring.

IEEE 802.11g

Others may consider the standard to be popular today IEEE 802.11g. The goal of creating this standard was to achieve speedy data transmission 54 Mbit/s.
Yak i IEEE 802.11b. IEEE 802.11g standard for robots in the 2.4 GHz frequency range. IEEE 802.11g offers both flexible and flexible data transmission rates:

obov'yazkovi -1; 2; 5.5; 6; eleven; 12 and 24 Mbit/s;
maybe - 33; 36; 48 n 54 Mbit/s.

To access such indicators, coding is required using an additional sequence of additional codes (SBC). Orthogonal Frequency Multiplexing Method (OFDM), Hybrid Coding Method (HCC-OFDM) and Dual Packet Coding Method (PBCC).

It should be noted that the same fluidity can be achieved using different methods, but the transmission fluidity can only be achieved using other methods. SBC OFDM, and possible discounts for additional methods of SSK-OFDM and RVSS.

The advantage of possessing the IEEE 802.11g standard is the same as possessing IEEE 802.11b. You can easily use a computer with an IEEE standard edge card. 802.11b for robots with an access point to the IEEE 802.11g standard. And by chance. In addition, the complexity of this standard is significantly lower than that of the IEEE 802.11a standard.

IEEE 802.11h

Standard IEEE 802.11h It is divided into methods for effectively controlling the intensity of transmission, selecting non-specific transmission frequencies and generating unnecessary sounds. We can introduce some new algorithms to the access protocol to the middle MAS(Media Access Control, central access control), as well as physical compliance with the IEEE 802.11a standard.

We are primarily concerned with the fact that in some countries the range 5 GHz Vikorist is used for broadcasting satellite television, for radar tracking behind objects, which can introduce changes into the transmission of drone-free surveillance.

Sense robot algorithms according to the IEEE 802.11h standard. that when broken signals (interference) are detected, droneless tracking (or transmission) computers can dynamically move to a different range, and reduce or increase the intensity of transmissions. This allows you to more effectively organize the work of street and office radio measurements.

IEEE 802.11i

Standard IEEE 802.11i divisions specifically to improve the safety of the robot-free line. This means the creation of various encryption and authentication algorithms, security functions when exchanging information, the ability to generate keys, etc.:

AES(Advanced Encryption Standard, advanced data encryption algorithm) - an encryption algorithm that allows you to use keys of 128.15)2 and 256 bits;
RADIUS(Remote Authentication Dial-In User Service) - an authentication system with the ability to generate keys for each session and manage them. which includes algorithms for checking the validity of packages, etc.;
TKIP(Temporal Key Integrity Protocol) – data encryption algorithm;
WRAP(Wireless Robust Authenticated Protocol) - data encryption algorithm;
RSMR(Counter with Cipher Block Chaining Message Authentication Code Protocol) - data encryption algorithm.

IEEE 802.11j

Standard IEEE 802.11j divisions specifically for the development of dartless lines in Japan, and for work in the additional radio frequency range 4.9-5 GHz. The specification is intended for Japan and expands the 802.11a standard with an additional 4.9 GHz channel.

At the moment, the frequency of 4.9 GHz is considered as an additional range for the US radio station. From official sources, it is clear that this range is being prepared for use by the civil and national security authorities.
This standard expands the range of robotic devices to the IEEE 802.11a standard.

IEEE 802.11n

Today's standard IEEE 802.11n The most extensive of all standards that are used for dartless measurements.

The basis of the 802.11n standard:

Increased transmission speed;
Rozshirennya zone pokrittya;
Increased reliability of signal transmission;
Increased capacity.

802.11n devices can operate in one of two bands 2.4 chi 5.0 GHz.

On the physical level (PHY), a thorough processing of the signal and modulation has been implemented, and the possibility of one-hour signal transmission through several antennas has been added.

On the edge layer (MAC), an efficient use of the available bandwidth has been implemented. At the same time, this makes it possible to increase the theoretical speed of data transmission up to 600 Mbit/s- Increased more than ten times, compared to 54 Mbit/s standard 802.11a/g (at this time, these devices are already considered old).

In fact, the productivity of a drone-free local network depends on numerical factors, such as the data transmission center, radio frequency, placement of devices and their configuration.

When implementing 802.11n devices, it is important to understand what features are implemented in that standard and how they relate to, and interact with, the legacy 802 standard. 11a/b/g dartless measures.

It is important to understand what additional features of the 802.11n standard are implemented and supported in new drone-free devices.

One of the main points of the 802.11n standard is the advancement of technology. MIMO(Multiple Input Multiple Output, Multiple channel input/output).
Using additional MIMO technology, the ability to simultaneously receive/transmit multiple data streams through multiple antennas instead of one is realized.

For example, an access point with two transmitting and three receiving antennas is "2x3" MIMO-we'll build it. I will describe this standard in a later report.

IEEE 802.11g

The standard drone-free standard does not exactly describe the roaming rules for moving a client from one zone to another. We hope to work with the standard IEEE 802.11

IEEE 802.11ac standard

He expects gigabyte drone-free liquids for his companions.

Initial draft technical specification 802.11ac Confirmed by the working group (TGac) last year. It's time for ratification Wi-Fi Alliance Find yourself at the end of this fate. Doesn't care about those who are standard 802.11ac still in the draft stage and may yet be ratified Wi-Fi Alliance and IEEE. We are already starting to look at gigabit Wi-Fi products available on the market.

Characteristics of the new generation of Wi-Fi 802.11ac:

WLAN 802.11ac Vikorist introduces a range of new methods to achieve large productivity gains while theoretically boosting gigabyte capacity and ensuring high throughput capacities, such as:

6GHz Smuga
High modulation density up to 256 QAM.
Larger bandwidth – 80MHz for two channels or 160MHz for one channel.
Up to eight Multiple Input Multiple Output space streams.

Low-power MIMO 802.11ac is widely available and presents new challenges for engineers to work with the standard. Next we will discuss the problems and available solutions that will help develop new products that are based on this standard.

Shirsha Smuha pass:

802.11ac has a higher bandwidth of 80 MHz, or the forward 160 MHz is equalized from the front to 40 MHz for the 802.11n standard. Greater bandwidth increases the maximum bandwidth of digital communication systems.

Among the largest design and selection tasks are the generation and analysis of high-bandwidth signals for 802.11ac. It is necessary to test the equipment, the specific equipment of 80 or 160 MHz to verify the transmission, reception and components.

To generate 80 MHz signals, many RF signal generators do not have high enough sampling rates to maintain the typical minimum 2X oversampling ratio that will result in the desired images. signals Vikorist's correct filtering and resampling of the signal from the Waveform file can generate 80 MHz signals with good spectral characteristics and EVM.

To generate signals 160 MHz wide range AWG signal generator. Such as Agilent 81180A, 8190A, it is possible to create analog I/Q signals using the same technology.

These signals can be reduced to a different I/Q. This is the input of the vector signal generator for reversing the RF frequency. In addition, it is possible to combine 160 MHz signals with 80 +80 MHz vicors, which supports the standard for creating two 80 MHz segments in either MCG or ESG signal generators, then combining radio signals.

MIMO:

MIMO The use of multiple antennas improves the productivity of the coupling system. You could have some Wi-Fi access points that have more than one antenna. How to erase them is that routers use MIMO technology.

Checking the MIMO design means changing it. Multiple channel generation and signal analysis can be used to determine the performance of MIMO devices. I provide assistance in troubleshooting problems and revising projects.

Linearity booster:

Linearity is a characteristic that is enhanced. In addition, the output signal of the booster is deprived of the correct input signal in the world of growth. In reality, strong linearity is linear until the boundary, after which the output is present.

There are a lot of methods for improving the linearity of the booster. Digital advancement is one such technology. Automation of software design, as SystemVue provides software. This will simplify and automate the digital design of the anterior curvatures to increase tension.

Insanity from previous versions

The desire for the 802.11n standard has already been widely debated. All the same, many routers and drone-free devices use older protocols. There are such types as 802.11b and 802.11g, although there are really few of them. Also at the hour of transition up to 802.11ac, Old Wi-Fi standards will be supported and the gateway will be ensured.

Leave it all. If you still have food, you can kindly write to me,

Hello everyone! Today we are talking again about routers, drone-free monitoring, technology...

Having prepared an article in order to find out what is behind such unintelligent letters b/g/n, which can be observed when setting up a Wi-Fi router, or when purchasing a device (Wi-Fi characteristics, for example 802.11 b/g). And what is the difference between these standards.

Now we will try to find out what the settings are and how to change them in the settings of the router and why change the drone-free tracking mode.

To mean b/g/n– this is the robotic mode of dart-less tracking (Mode).

802.11n devices can operate in one of two bands 2.4 chi 5.0 GHz.

On the physical level (PHY), a thorough processing of the signal and modulation has been implemented, and the possibility of one-hour signal transmission through several antennas has been added.

In fact, the productivity of a drone-free local network depends on numerical factors, such as the data transmission center, radio frequency, placement of devices and their configuration. When implementing 802.11n devices, it is important to understand what features are implemented in that standard and how they relate to, and interact with, the legacy 802 standard. 11a/b/g dartless measures. It is important to understand what additional features of the 802.11n standard are implemented and supported in new drone-free devices.

Standard 802.11n means different antenna configurations “MXN”, starting with "1x1" before "4x4"(The most widely used configurations today are “3x3” or “2x3”). The first number (M) indicates the number of transmitting antennas, and the other number (N) indicates the number of receiving antennas. For example, an access point with two transmitting and three receiving antennas is "2x3" MIMO-we'll build it. I will describe this standard in a later report.

One of the most important settings for the drone-free range is “Robot Mode”, “Dartless Range Mode”, “Mode” etc. The name depends on the router, firmware, or mobile panels. This item in the router settings allows you to set the Wi-Fi mode (802.11). The most common mode is b/g/n. Well, if you have a dual-band router.

To determine which mode is better to select in the settings of the router, you first need to figure out what is included in the settings. I think we won’t show a screenshot of these settings on the TP-Link router application. For the range 2.4 and 5 GHz.

Currently there are 4 main modes: b/g/n/ac. The main function is maximum connection fluidity. Please note that the speed is as fast as I can write about below, which is the maximum possible speed (in one channel). Yaku can be seen in ideal minds. In real minds, the fluidity of connection is much lower.

IEEE 802.11– this is a set of standards on which all Wi-Fi networks operate. In essence, this is Wi-Fi.

Let's take a closer look at the skin standard (Essentially, this version of Wi-Fi):

802.11a– Even though I wrote about several main regimes, I didn’t look at them. This is one of the first standards, operating in the 5 GHz range. Maximum speed 54 Mbit/s. Not the most popular standard. She's old already. The 5 GHz band already follows the ac standard.
802.11b– operates in the 2.4 GHz band. Speed up to 11 Mbit/s.
802.11g– we can say that the 802.11b standard is more current and updated. It also works in the 2.4 GHz range. The speed is already up to 54 Mbit/s. Sumisnyy 802.11b. For example, if your device can operate in this mode, it will connect without problems to the same mode as those operating in mode B (the older one).
802.11n- The most popular standard today. Speed up to 150 Mbit/s in the 2.4 GHz range and up to 600 Mbit/s in the 5 GHz range. Sustainability from 802.11a/b/g.
802.11ac– a new standard that works better in the 5 GHz range. Transfer speed up to 6.77 Gbit/s (obviously 8 antennas and in MU-MIMO mode). This mode is only available on dual-band routers, which can transmit data in the 2.4 GHz and 5 GHz range.

Fluidity of connection

As practice shows, most often the configuration of b/g/n/ac is changed by increasing the speed of the Internet connection. Let me immediately explain how this works.

Take the most popular standard 802.11n in the 2.4 GHz band, with a maximum bandwidth of 150 Mbit/s. This number itself is most often indicated on the box with the router. So it might just say 300 Mbit/s, or 450 Mbit/s. This should be located in the presence of several antennas on the router. With only one antenna, the router operates in one stream and speeds up to 150 Mbit/s. If there are two antennas, then two streams and speed are multiplied by two - we can take up to 300 Mbit/s, etc.

It's all just numbers. For real people, Wi-Fi speed when connected in 802.11n mode will be 70-80 Mbit/s. Liquidity depends on a large number of different factors: interruptions, signal strength, productivity and demand on the router, setup, etc.

There are fragments of stench in many versions of the web interface, so let’s take a look at a few of them. If your version has a light web interface like the one in the screenshot below, open the “Wi-Fi” section. There will be an item “No-Gun Mode” with several options: 802.11 B/G/N mixed, and also N/B/G.

Or say it like this:

Setting up "802.11 Mode".

Radio frequency range on the Netis router

Open the settings page in your browser at the address http://netis.cc. Then go to the “No-Gun Mode” section.

There will be a menu "Radio Frequency Range". You can change the Wi-Fi connection standard. The settings are set to "802.11 b+g+n".

Nothing complicated. Don’t forget to save as much as you have done.

Setting up Wi-Fi edge mode on a Tenda router

The settings can be found in the section “No-gun mode” – “Basic WIFI setup”.

Item "Merezhevy mode".

You can set it to mixing mode (11b/g/n) and okremo. For example, less than 11n.

If you have a different router, or setup

It is simply impossible to provide specific dates for all devices and software versions. If you need to change the standard of the drone-free range, and you have not found your device in the statistics, look at the adjustment in the section called “Dartless range”, “WiFi”, “Wireless”.

If you don’t know, write the model of your router in the comments. You should also attach a screenshot from the control panel. I’ll show you how to joke and tune up.

802.11n - data transfer mode, the real speed is approximately much lower than 802.11g (54 Mbit/s). However, it is important to note that the device that sends and receives operates in 802.11n mode.

802.11n devices operate in the frequency range 2.4 - 2.5 or 5 GHz. The frequency is indicated in the documentation for the device or packaging. Radius of action - 100 meters (can be adjusted at speed).

IEEE 802.11n - a fast robotic Wi-Fi mode, faster than 802.11ac (which is an incredibly cool standard). The combination of 802.11n with the older 802.11a/b/g is possible if the same frequency and channel are selected.

You may think that I’m wonderful, but I don’t like Wi-Fi - I don’t know why, but it seems to be stable, but it’s not as stable as darty (vita pair). Maybe because I don't have a USB adapter. I want to take my Wi-Fi PCI card from the future, I am sure that everything is stable there)) I am also talking about those that Wi-Fi USB without an antenna and the speed through the power of the walls will be reduced.. Otherwise, there are darts lying around our apartment , and I am fit - not too much and easily..))

As I understand it, 802.11n is not a bad standard, since it also includes the characteristics of 802.11a/b/g.

However, one thing is clear – 802.11n is not inferior to the latest standards. As I understand it, this is the main reason why 802.11n is not a particularly popular standard, even having been introduced in 2007. After all, there is still madness - I wrote about it below.

Some characteristics of other standards:

There are a lot of standards and some of them serve their purpose:

Watch, 802.11p axis - indicates the type of devices that, within a kilometer radius, travel with a speed of no more than 200 km. Do you see?)) The axis is technology!!

802.11n and router speed

Surprisingly, such a situation is possible - you will need to increase the speed of your router. What is it timid? Your router can easily support the IEEE 802.11n standard. You need to open the settings, and here you will find the option to set the standard so that the devices can work in that mode. If you have an ASUS router, then the setup can look something like this:

Essentially, the name is the letter N. If your company is TP-Link, then you can set it up like this:

That's all for the router. I understand that there is not enough information - but now you know that the router is configured, and how to connect to the router. I only know that you need to open the address... it’s 192.168.1.1, apparently.

If you have a laptop, you can support the IEEE 802.11n standard. It’s important to install this if you, for example, are creating an access point from your laptop (as a matter of fact). Open Device Manager, press the Win + R buttons and paste this command:

Then find your Wi-Fi adapter (it can be called a Broadcom 802.11n edge adapter) - right-click and select Power:

Go to the Additional tab and find the item 802.11n Direct Connection Mode, select Enable:

Settings may be different - Wireless Mode, Wireless Type, Wi-Fi Mode, Wi-Fi type. It is necessary to enter the transmission mode. This is the effect of the speed plan, as I already wrote, in my opinion, as it is offensive to install the 802.11n standard.

We know such important information as crazy:

Read about the insanity and wealth of important information about the 802.11 standard here:

There really is a lot of valuable information there, the Raja would still be amazed.

AdHoc Support 802.11n what is it? Do you need to mix anything?

AdHoc Support 802.11n or AdHoc 11n - support for AdHoc clock monitoring, when connected between different devices. Vikorist for prompt transmission. I don’t know any information about those who can organize distribution to the Internet using AdHoc (although everything is possible).

Officially AdHoc offers speed equal to the 11g standard - 54 Mbit/s.

The best moment to discover is the speed of Wi-Fi 802.11g, as I already wrote – 54 Mbit/s. However, it turns out that 54 is not a total number, so it is not receiving and sending. So, in one day the speed is 27 Mbit/s. But that’s not all - 27 Mbit / s is the channel speed that is possible for ideal minds, it is impossible to achieve them - 30-40% of the channel still adds up to changes in the appearance of mobile phones, all kinds of upgrades, smart TVs with Wi-Fi and otherwise . The resulting speed may actually be 18-20 Mbit/s, or maybe less. I am not convinced - but it is possible that other standards are at issue.

So do you need to turn on anything? There is no need to go out without any need. Also, if I understand correctly, then when turned on, a new local network will be created and, perhaps, it will still be possible to organize the Internet in it. In other words, it is possible that using AdHoc you can create a Wi-Fi access point. Having marveled so much on the Internet - it’s still possible))

I just remember that I bought my own Wi-Fi adapter from D-Link (this model was D-Link N150 DWA-123) and there was no support for the creation of an access point. Alas, it’s Chinese.. it’s even better.. I found out that you can install special unofficial drivers on it, napiv-curves, and using them you can create an access point.. I axis is an access point right tsyuvala yak bi for further help AdHoc, unfortunately I don’t remember for sure - but she was doing more than bad.

Adjustment of Ad Hoc at the authorities of the border

Please note that QoS is a technology that divides traffic in terms of priorities. Ensures the necessary high rate of packet transmission for important processes/programs. In simple words, QoS allows you to give high priority to programs that require data transmission - online games, VoIP telephony, streaming, streaming, etc., Skype and Viber are also connected.

802.11 Preamble Long and Short – what is this setup?

So, this adjustment is a whole science. The part of the frame that is transmitted by the 802.11 module is called the preamble. There may be a long (Long) or short (Short) preamble and may not be indicated in the configured 802.11 Preamble (or Preamble Type). The long preamble is a 128-bit synchronization field, the short one is 56-bit.

802.11 devices that operate on the 2.4 GHz frequency require long preambles when receiving and transmitting. 802.11g devices must deal with long and short preambles. For 802.11b devices, short preambles are optional.

The values in the configured 802.11 Preamble can be Long, Short, Mixed mode, Green field, Legacy mode. I’ll say it straight away - it’s best not to ignore adjustments unless necessary and lose importance on the settings or the availability of selecting Auto (or Default).

What do the Long and Short modes mean? We have already learned more. Now briefly about other modes:

Legacy mode. Mode for exchanging data between stations with the same antenna.
mixed mode. Transmission mode between MIMO systems (broadcast, or even more so than Green Field), and between call stations (at least, while maintaining high speed). The MIMO system designates the packet as it is received.
Green field. Transmission is possible between multiple antenna devices. When transmitting by a MIMO system, the originating stations switch to the same channel to avoid conflicts. The mode of receiving data from devices that operate in the most important two modes is possible, but the transmission axis to them is not. It is important to turn off single-antenna devices during the transmission process, thereby preserving high transmission speed.

Support MIMO What is it?

Just a note. MIMO (Multiple Input Multiple Output) is a type of data transmission, with which the method of spatial encoding of the signal increases the channel and data transmission occurs with several antennas at the same time.

20.10.2018

The Wi-Fi (Wireless Fidelity) protocol was developed back in 1996. It was initially used to create local connections, but gained greatest popularity as an effective method for connecting smartphones and other portable devices to the Internet.

Over the course of 20 years, the one-name alliance has grown into a single generation of connections, promoting the skin fate of Sweden and the functionalities of its renovation. They are described by 802.11 standards as defined by the IEEE (Institute of Electrical and Electronics Engineers). The group includes a number of protocol versions that enhance the speed of data transfer and support for additional functions.

The highest Wi-Fi standard available for all purposes. Supporting devices exchange data at a frequency of 2.4 GHz. The transmission speed became less than 1 Mbit/s. Devices were also offered with additional speed up to 2 Mbit/s. Vіn was actively vikorist for only 3 years, after which he was improved. The current Wi-Fi standard is indicated by a letter after the leading number (802.11a/b/g/n).

One of the first updates to the Wi-Fi standard came in 1999. By completely sub-frequency (up to 5 GHz), engineers were able to achieve theoretical speeds of up to 54 Mbit/s. Without taking away the wide expansion of the veins, the fragments are in themselves absurd with other versions. Devices that support this, for work in the range at 2.4 GHz, are to blame. Smartphones with Wi-Fi 802.11a are bad.

Wi-Fi standard IEEE 802.11b

Another early interface update that came out in parallel with version a. The frequency remained unchanged (2.4 GHz), but the speed was increased to 5.5 or 11 Mbit/s (depending on the device). Until the end of the first decade of the 2000s, this was the widest standard for dartless measurements. The ingenuity of the old version, as well as its great coverage radius, ensured its popularity. Regardless of new versions, 802.11b is supported by almost all modern smartphones.

Wi-Fi standard IEEE 802.11g

A new generation of Wi-Fi protocol was introduced in 2003. Retailers have overloaded the data transmission frequencies, which is why the standard turned out to be completely different from the previous ones (older devices ran at speeds of up to 11 Mbit/s). Transfer speed has increased to 54 Mbit/s, which was the same until recently. All modern smartphones use 802.11g.

Wi-Fi standard IEEE 802.11n

In 2009, the Wi-Fi standard was updated on a larger scale. The new version of the interface has increased speed (up to 600 Mbit/s), saving money from the previous ones. To make it possible to work with 802.11a, as well as to combat the over-prevalence of the 2.4 GHz band, the frequency support of 5 GHz (parallel to 2.4 GHz) was shifted.

The possibilities for configuring the network have been expanded and the number of supports that can be connected at once has been increased. It has become possible to communicate in multi-streaming MIMO mode (parallel transmission of multiple data streams at the same frequency) and combine two channels to communicate with one device. The first smartphones based on this protocol were released in 2010.

Wi-Fi standard IEEE 802.11ac

In 2014, the new Wi-Fi standard IEEE 802.11ac was approved. This has become a logical extension of 802.11n, which provides a tenfold increase in speed. It is now possible to connect up to 8 channels (20 MHz each) simultaneously – the theoretical capacity has increased to 6.93 Gbit/s. 24 times swedish, lower 802.11n.

The 2.4 GHz frequency was likely to be used due to the limited range and the impossibility of combining more than 2 channels. The IEEE 802.11ac Wi-Fi standard operates in the 5 GHz band and is limited to 802.11n devices (with a frequency of 2.4 GHz), but operation with earlier versions is not guaranteed. Today, not all smartphones support it (for example, rich budget employees on MediaTek do not have support).

Other standards

Refer to IEEE 802.11 versions marked with different letters. Or they either make minor amendments and additions to exceed the standards, or add specific functions (for the possibility of interaction with other radio measurements or security). You can see 802.11y, which is a non-standard frequency of 3.6 GHz, as well as 802.11ad, which covers the 60 GHz range. First creations to ensure a range of up to 5 km per rakhunok vikoristannaya clean range. The other (also known as WiGig) is used to ensure maximum (up to 7 Gbit/s) connection speed on small distances (between rooms).

What is the best Wi-Fi standard for a smartphone?

All current smartphones have a Wi-Fi module and are licensed to work with several versions of 802.11. As a rule, all the same standards are met: b, g and n. However, the work with the rest can often be implemented at a frequency of 2.4 GHz. Devices that currently operate within the 802.11n 5 GHz band are also supported by the 802.11a bandwagon.

Increasing frequencies mean greater speed of data exchange. As soon as the winter season changes, it becomes easier for them to pass through a crisis. Through this theoretical range, the connection will be 2.4 GHz, lower than 5 GHz. However, in practice the situation is slightly different.

The frequency of 2.4 GHz turned out to be free, so the consumer electronics are the same. Besides Wi-Fi, whose range operates Bluetooth devices, such as wireless keyboards and bears, the magnetrons of low-frequency ovens are also used. Therefore, in places where the Wi-Fi network operates, the number of cross-codes reduces the range advantage. The signal can be caught from hundreds of meters away, but the bandwidth will be minimal, and the consumption of data packets will be greater.

The 5 GHz range is wider (from 5170 to 5905 MHz) and less demanding. Therefore, the worst need to change (the wall, the furniture, the body of a person), then in the minds of direct visibility they will ensure a lasting connection. The inability to effectively pay the wall turns into an advantage: you won’t be able to harm your neighbor’s Wi-Fi, but it won’t affect your router or smartphone.

However, keep in mind that to achieve maximum speed, you need a router that follows this very standard. In other situations, it is still not possible to download more than 150 Mbit/s.

There is a lot to be found in the router and this type of antenna. The antennas of the adaptive type are divided so that they indicate the location of the smartphone and supply a new direct signal that reaches further, lower types of antennas.