Wireless Fiber Siklu
The data transfer rates provided by wireless communication systems are constantly increasing. Solutions are emerging on the market that can replace a fiber-optic channel without the need for laying the fiber itself. One of these solutions is the EH-5500FD system developed by Siklu, which provides 5 Gbit / s speed when operating in the E-band.
Before telling more about this product - a couple of words about the company itself and the E-band. Siklu has greatly changed the concept of wireless gigabit transport, increasing the speed and reducing the cost of transmitting a unit of information. The company was founded in 2008 with the ambitious goal of creating an inexpensive wireless communication system that addresses bandwidth problems. Its specialists have developed their own microcircuits, where all the necessary radio transmission functions are implemented, as well as broadband modem and antennas. This allowed us to offer very high-speed and low-cost solutions. (In fact, the only component that Siklu buys from third-party vendors is a network processor that performs the functions of L2 / L3.) Siklu solutions are easily scalable and can be used for a wide range of tasks. They are also notable for simplicity of installation and maintenance, which simplifies and accelerates the process of deployment and development of the network infrastructure.
Siklu is actively developing E-band wireless solutions. This range includes the frequency bands 71–76 GHz and 81–86 GHz, for which in most countries, including Russia, there is no need to obtain frequency licenses - simply registering equipment is sufficient. License-free status is the main, but far from the only advantage of this range. It can use a wide band that allows you to get a very high transmission speed. At the same time, gigabit speeds are achieved even when operating in the 500 MHz band. And the narrow directivity of the antennas of radio-relay stations (PPC) operating in the E-band ensures a low level of interference for other radio systems.
')
The E-band is characterized by the presence of a transparency window, in which there is a minimum of attenuation on the molecules of oxygen and water vapor, due to which high-speed data transmission becomes possible. At the same time, in this range, the attenuation of hydrometeors is high, which significantly reduces the range. The E-band wave is about 4 mm long and can be scattered by particles of similar size, for example, large raindrops. Therefore, only rain showers with large drops have an impact on the performance of the corresponding X-ray diffraction patterns. Smaller objects, such as small raindrops, grains of sand, dust particles, water suspension (fog), etc., are too small to cause wave dispersion, and therefore less critical for the operation of communication systems in the considered range.
But back to our "main character" - the system EH-5500FD. As befits a “fiber change”, it provides transparent forwarding of traffic at the L1 level. Network equipment for transmitting traffic is connected to it via a standard SFP + transceiver for 10 Gigabit Ethernet network. This equipment can be various aggregation, border or demarcation devices, Ethernet routers and switches, etc. It is also important that, like fiber, in addition to high speed, the EH-5500FD system provides a very low latency - only 5 μs.
Interfaces EH-5500FD:
1 - Grounding
2 - DC power supply (45 W)
3 - AUX Port
4 - Ethernet 100 / 1000Base-T (RJ45) for control and powering over PoE (PoE In)
5 - 10G Ethernet SFP +
In addition to the 10G Ethernet SFP +, the EH-5500FD has another Ethernet port. It is designed for copper-wire connections at speeds of 100/1000 Mbit / s and serves to control and provide power over an Ethernet (PoE) network. PoE support can greatly simplify the deployment of a system where there is no power source nearby. There is also a connector for local DC power supply. Having two options for powering the device increases flexibility when using it in projects.
Another connector available on the EH-5500FD, the AUX port, is used to connect a digital voltmeter when the antenna is pointing. Actually, to perform this procedure, no special tools are needed, a voltmeter is sufficient. When this device is connected to the AUX port, the device is switched to the Alignment Mode, and the voltmeter itself displays the received signal level (RSSI) in dBm (or rather, voltage from 0 to 1 V, the value of which corresponds to the RSSI module in dBm. For example, for RSSI - 53 dBm voltmeter counts from contacts 0.53 V). Reading these readings and moving the antenna, it is easy to position it to obtain the maximum signal level. Everything is easy and convenient.
Operating in the E-band, the EH-5500FD system can operate three channels up to 1,250 MHz wide. In the base case, the transmission speed of 2 Gbit / s in full duplex mode is provided. By purchasing an additional license, you can programmatically increase the speed to a maximum of 5 Gbit / s.
The EH-5500FD can use the same antennas and mounting kits as other Siklu solutions. You can choose from three antenna options:
The use of small-diameter antennas is especially important when installing in city centers, where it is very important to ensure that communication systems are as inconspicuous as possible and do not spoil the overall appearance.
As already mentioned, SFP + transceivers are used to connect to network equipment. Siklu itself offers two options for such a transceiver: for multimode fiber, the connection range is up to 300 m; and for single-mode fiber - a range of 10 km. Transceivers from other suppliers, such as Finisar, can also be used.
The maximum speed of 5 Gbps is achieved using 32QAM modulation. At the same time, the maximum communication range when using a half-foot antenna is 2 km, a one-foot one is 3 km, and a two-foot one is 3.1 km. These data are given by the manufacturer for the rain zone K, where precipitation is significantly more intense than zone E, to which most of the territory of the Russian Federation belongs. At the same time, the estimated channel availability ratio is 99.9%.
In general, the E-band PPC span length depends on the region of deployment, the required speed of transmission and the availability ratio of the communication channel. If you need to increase the availability factor and / or increase the communication range, you can switch to low-level modulations, providing higher noise immunity, but reducing data transfer speeds. For example, using QPSK1 modulation with an availability level of 99.9%, 2 Gbps can be achieved at a range of 2.8 km (half-foot antenna) to 6.6 km (two-foot antenna).
If you need to significantly increase availability, up to 99.99%, you will still have to sacrifice speed. In this case, it will be necessary to switch to BPSK1 modulation, and the 210 Mbit / s channel will be provided at a distance of 2.2 km, 2.9 km and 3.8 km using a half-foot, one-foot and two-foot antenna, respectively.
The EH-5500FD implements an adaptive mechanism for controlling the transmission rate and the used coding algorithms (FEC coding coefficient) and modulation upon changing weather conditions. This means, for example, that with the onset of precipitation, the Siklu system will switch to lower level modulation and / or increase the proportion of redundant bits used for forward error correction (FEC). As a result, the speed will, of course, decrease, but the connection will be maintained, and support will be guaranteed for the most important applications (for example, voice communication, transactional systems, control devices), while lower priority (e-mail, streaming video, etc.) will be denied data wirelessly.
The use of this adaptive technology ensures maximum utilization of the resources of the wireless channel, as well as its constant availability for critical applications. In general, today the dependence of the characteristics of the wireless channel in the millimeter range of weather conditions is becoming less important. The fact is that modern management systems, especially software-defined WAN controllers (SD-WAN), are able to flexibly redistribute traffic across all available channels, taking into account the priority of applications for business. At the same time, an expensive wired channel can be rented only for the time when it is possible to reduce the speed of transmission over a wireless channel (due to heavy rain). Such a situation already looks quite real: having received a weather forecast that predicts heavy rain, the network controller can independently insure itself by requesting the rental of a wired or other (insensitive to rain) channel for this time.
There are many situations when a high-speed wireless channel may be not only useful, but also the only possible solution to the problem of providing communication.
Imagine, for example, that it is necessary to provide high-speed communication between buildings, between which there is a serious obstacle to the laying of optics: a busy transport highway, a river, etc. In this case, the Siklu solution becomes indispensable. Own direct wireless channel can become the main one, and as a reserve, you can use connections through your carrier network. Another situation is possible: the channel built on the Siklu equipment will provide redundancy of the existing wired one.
So, the considered technical solution can be used for various purposes: the organization of the "last mile" and a variety of layouts, the reservation of a wired urban network, the organization of time channels. It is effective for connecting video cameras, base stations, including new generation microcell, Wi-Fi access points, etc. No need to obtain a license and an attractive price ($ 6000 in the GPL), coupled with high data transfer speed and small system size are very serious advantages opt for the wireless "fiber".
Before telling more about this product - a couple of words about the company itself and the E-band. Siklu has greatly changed the concept of wireless gigabit transport, increasing the speed and reducing the cost of transmitting a unit of information. The company was founded in 2008 with the ambitious goal of creating an inexpensive wireless communication system that addresses bandwidth problems. Its specialists have developed their own microcircuits, where all the necessary radio transmission functions are implemented, as well as broadband modem and antennas. This allowed us to offer very high-speed and low-cost solutions. (In fact, the only component that Siklu buys from third-party vendors is a network processor that performs the functions of L2 / L3.) Siklu solutions are easily scalable and can be used for a wide range of tasks. They are also notable for simplicity of installation and maintenance, which simplifies and accelerates the process of deployment and development of the network infrastructure.
Siklu is actively developing E-band wireless solutions. This range includes the frequency bands 71–76 GHz and 81–86 GHz, for which in most countries, including Russia, there is no need to obtain frequency licenses - simply registering equipment is sufficient. License-free status is the main, but far from the only advantage of this range. It can use a wide band that allows you to get a very high transmission speed. At the same time, gigabit speeds are achieved even when operating in the 500 MHz band. And the narrow directivity of the antennas of radio-relay stations (PPC) operating in the E-band ensures a low level of interference for other radio systems.
')
The E-band is characterized by the presence of a transparency window, in which there is a minimum of attenuation on the molecules of oxygen and water vapor, due to which high-speed data transmission becomes possible. At the same time, in this range, the attenuation of hydrometeors is high, which significantly reduces the range. The E-band wave is about 4 mm long and can be scattered by particles of similar size, for example, large raindrops. Therefore, only rain showers with large drops have an impact on the performance of the corresponding X-ray diffraction patterns. Smaller objects, such as small raindrops, grains of sand, dust particles, water suspension (fog), etc., are too small to cause wave dispersion, and therefore less critical for the operation of communication systems in the considered range.
But back to our "main character" - the system EH-5500FD. As befits a “fiber change”, it provides transparent forwarding of traffic at the L1 level. Network equipment for transmitting traffic is connected to it via a standard SFP + transceiver for 10 Gigabit Ethernet network. This equipment can be various aggregation, border or demarcation devices, Ethernet routers and switches, etc. It is also important that, like fiber, in addition to high speed, the EH-5500FD system provides a very low latency - only 5 μs.
Interfaces EH-5500FD:
1 - Grounding
2 - DC power supply (45 W)
3 - AUX Port
4 - Ethernet 100 / 1000Base-T (RJ45) for control and powering over PoE (PoE In)
5 - 10G Ethernet SFP +
In addition to the 10G Ethernet SFP +, the EH-5500FD has another Ethernet port. It is designed for copper-wire connections at speeds of 100/1000 Mbit / s and serves to control and provide power over an Ethernet (PoE) network. PoE support can greatly simplify the deployment of a system where there is no power source nearby. There is also a connector for local DC power supply. Having two options for powering the device increases flexibility when using it in projects.
Another connector available on the EH-5500FD, the AUX port, is used to connect a digital voltmeter when the antenna is pointing. Actually, to perform this procedure, no special tools are needed, a voltmeter is sufficient. When this device is connected to the AUX port, the device is switched to the Alignment Mode, and the voltmeter itself displays the received signal level (RSSI) in dBm (or rather, voltage from 0 to 1 V, the value of which corresponds to the RSSI module in dBm. For example, for RSSI - 53 dBm voltmeter counts from contacts 0.53 V). Reading these readings and moving the antenna, it is easy to position it to obtain the maximum signal level. Everything is easy and convenient.
Operating in the E-band, the EH-5500FD system can operate three channels up to 1,250 MHz wide. In the base case, the transmission speed of 2 Gbit / s in full duplex mode is provided. By purchasing an additional license, you can programmatically increase the speed to a maximum of 5 Gbit / s.
The EH-5500FD can use the same antennas and mounting kits as other Siklu solutions. You can choose from three antenna options:
- half foot (16 cm) with 38 dBi gain
- foot (31 cm) - 43 dBi
- two feet (65 cm) - 50 dBi.
The use of small-diameter antennas is especially important when installing in city centers, where it is very important to ensure that communication systems are as inconspicuous as possible and do not spoil the overall appearance.
As already mentioned, SFP + transceivers are used to connect to network equipment. Siklu itself offers two options for such a transceiver: for multimode fiber, the connection range is up to 300 m; and for single-mode fiber - a range of 10 km. Transceivers from other suppliers, such as Finisar, can also be used.
The maximum speed of 5 Gbps is achieved using 32QAM modulation. At the same time, the maximum communication range when using a half-foot antenna is 2 km, a one-foot one is 3 km, and a two-foot one is 3.1 km. These data are given by the manufacturer for the rain zone K, where precipitation is significantly more intense than zone E, to which most of the territory of the Russian Federation belongs. At the same time, the estimated channel availability ratio is 99.9%.
In general, the E-band PPC span length depends on the region of deployment, the required speed of transmission and the availability ratio of the communication channel. If you need to increase the availability factor and / or increase the communication range, you can switch to low-level modulations, providing higher noise immunity, but reducing data transfer speeds. For example, using QPSK1 modulation with an availability level of 99.9%, 2 Gbps can be achieved at a range of 2.8 km (half-foot antenna) to 6.6 km (two-foot antenna).
If you need to significantly increase availability, up to 99.99%, you will still have to sacrifice speed. In this case, it will be necessary to switch to BPSK1 modulation, and the 210 Mbit / s channel will be provided at a distance of 2.2 km, 2.9 km and 3.8 km using a half-foot, one-foot and two-foot antenna, respectively.
The EH-5500FD implements an adaptive mechanism for controlling the transmission rate and the used coding algorithms (FEC coding coefficient) and modulation upon changing weather conditions. This means, for example, that with the onset of precipitation, the Siklu system will switch to lower level modulation and / or increase the proportion of redundant bits used for forward error correction (FEC). As a result, the speed will, of course, decrease, but the connection will be maintained, and support will be guaranteed for the most important applications (for example, voice communication, transactional systems, control devices), while lower priority (e-mail, streaming video, etc.) will be denied data wirelessly.
The use of this adaptive technology ensures maximum utilization of the resources of the wireless channel, as well as its constant availability for critical applications. In general, today the dependence of the characteristics of the wireless channel in the millimeter range of weather conditions is becoming less important. The fact is that modern management systems, especially software-defined WAN controllers (SD-WAN), are able to flexibly redistribute traffic across all available channels, taking into account the priority of applications for business. At the same time, an expensive wired channel can be rented only for the time when it is possible to reduce the speed of transmission over a wireless channel (due to heavy rain). Such a situation already looks quite real: having received a weather forecast that predicts heavy rain, the network controller can independently insure itself by requesting the rental of a wired or other (insensitive to rain) channel for this time.
There are many situations when a high-speed wireless channel may be not only useful, but also the only possible solution to the problem of providing communication.
Imagine, for example, that it is necessary to provide high-speed communication between buildings, between which there is a serious obstacle to the laying of optics: a busy transport highway, a river, etc. In this case, the Siklu solution becomes indispensable. Own direct wireless channel can become the main one, and as a reserve, you can use connections through your carrier network. Another situation is possible: the channel built on the Siklu equipment will provide redundancy of the existing wired one.
So, the considered technical solution can be used for various purposes: the organization of the "last mile" and a variety of layouts, the reservation of a wired urban network, the organization of time channels. It is effective for connecting video cameras, base stations, including new generation microcell, Wi-Fi access points, etc. No need to obtain a license and an attractive price ($ 6000 in the GPL), coupled with high data transfer speed and small system size are very serious advantages opt for the wireless "fiber".
Source: https://habr.com/ru/post/342930/
All Articles