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Seeing that in the range Wireless LAN, Ubiquiti has made available products based on the new 802.11n standard, several customers ask me for information on this standard and on radio techniques MIMO (Multiple Input and Multiple Output) operating in both the 5GHz and 2.4GHz bands.
In the MIMO technique the data flow in transmission is divided between two or more antennas (usually two antennas, one with vertical polarization and one horizontal); the receiver picks up the received streams and reassembles them in the original stream. This technique allows to double the transmission speed, for the same time, double the information is transmitted. The use of multiple antennas that transmit the same signal provides a system of redundancy, and the reception capacity of the signal coming from different paths increases the reception quality, so compared to the 802.11g standard, a significant improvement in wireless coverage is obtained. The MIMO technology also allows to improve the passage of the radio signal through obstacles of various kinds.
The improvement of the OFDM encoding and the doubling of the communication channel from 20 MHz to 40 MHz brings the communication speed of 802.11n systems to 150Mbs. However, doubling the channel halves the number of available channels, so it is much more likely to have overlaps of channels between different systems by reducing the communication speed.
The 802.11n standard is compatible with the previous standards, this means that the 802.11a / b / g devices can communicate with the 802.11n ones, of course in this case the communication speed will be that of the lower standard, see post.
I have two offices connected to each other in WiFi at 2.4Mhz, wanting to increase the communication speed I thought I would switch to the 802.11n standard, I saw your Ubiquiti products, in particular the Rocket model, taking into account that the distance is about 70mt which type of antenna you recommend.
I would also like to know which antennas to use over a distance of 500mt.
Given the modest distance to cover (both 70mt and 500mt) I would not choose the model Rocket which requires external antennas and is suitable for covering long distances (up to 50 km). I would orient myself on the model Nano Station M, which in a single container suitable for outdoor use contains both the electronics and the 2 antennas for the MIMO transmission technique.
This product as stated by the manufacturer Ubiquiti, 150 Mbps real outdoor throughput and up to 15km range, it is certainly able to cover the distances you require, both 70m and 500m.
We are interested in purchasing two 5 GHz Ubiquity Rocket M and related antennas. The application is the data link between reception offices and camping offices, visible to each other, about 2 km away.
The radio section crosses a municipal road and a beach belonging to another property. Is this installation possible at a regulatory level?
Do we have to request licenses, permits, licenses?
Apart from the hardware structure, will there be flat-rate or annual costs for permits / licenses / fees due to someone?
What kind of antennas do you recommend?
Are ready-made cables from Rocket to antenna also available?
Are the devices in question available?If it is crossed with the public land signal and / or other properties at present, a general authorization is required which is a declaration to be sent to the Ministry of Communications referring to this post.
Given the distance to cover, I can recommend the use of a 90 ° sector MIMO antenna, see the data sheets on the Rocket, the antenna is complete with jumpers cables for connection.
Given the distance to cover 2Km, I recommend the Nano Station M model as an alternative to the Rocket, as already reported in a previous post.
As for availability and prices, consult the site, next to each item there is a symbol that indicates whether it is ready in stock or not. Ubiquiti products, if they are not available in stock, require an average of 2 weeks for delivery.
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