George Hardesty

Mar 012014
 
  • High QAM rate = more throughput
  • Lower modulation allow smaller antenna size.

Quadrature amplitude modulation (QAM) is an analog and a digital modulation scheme, used extensively as a modulation scheme for wireless digital telecommunication systems.  Arbitrarily high spectral efficiencies can be achieved with QAM by setting a suitable constellation size, limited only by the noise level and linearity of the communications channel.

Eband is limited to QAM rate of 64.

Feb 222014
 

Front to back ratio is the measure of directivity of a directional antenna: A ratio of the energy directed in a single direction, which is dependent on the radiation pattern to the energy wasted in or by the antenna. Increase the gain of a directional antenna, is the same as increasing the front to back ratio. The best front to back ratio of a directional antenna is a large dish antenna: 34dB.

 Posted by at 4:14 pm Antennas No Responses »
Feb 202014
 

The two main categories of WiFi antennas are omni directional and directional

Omni directional antennas provide 360 degree coverage in a donut shaped radiation pattern:  Providing the widest possible signal coverage for indoor and outdoor wireless applications:  Types of omni directional antennas include dipole (“rubber duck”) antennas that come as the default antenna on access points and routers, omni antennas found outdoors, and antenna arrays used on cellular towers.

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For WiFi inside an office building
To provide wireless coverage to an inside office space, use omni directional antennas that provide 360 degree wireless coverage. The style of antenna typically used is the ceiling mount omni directional antenna. The antenna gain pattern for the ceiling mount Omni directional antenna in this application is donut shaped with good vertical and well as horizontal coverage providing connectivity to WiFi devices including laptops, printers, tablets, and smart phones.
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I want to install WiFi in a campus environment (outside)
In this case you can use several directional antennas with an omni directional antenna at the central building to connect the building in the campus. This is called a point to multipoint network. As with any outdoor Wifi network, clear Line of Site is critical. Additionally, proper antenna alignment is necessary to ensure optimal signal quality.
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Connect one building to another building
In this design scenario you will need a directional antennas such as Yagi, or parabolic grid antennas. This is called a point to point wireless link. Each building should be outfitted with a directional antenna and the antennas need to point at each other inline. Also make sure there are no obstructions between the two antennas such as trees or buildings. Clear Line of Sight is critical.
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Provide WiFi access in an outdoor cafe
For an outdoor cafe use Omni directional antennas to provide 360 degree signal coverage to customers and employees. Try and mount the antenna as close to the center of the WiFi coverage area as possible. Also remember that if the Omni antenna you use has too much gain, then the users beyond the cafe area will tend to get better signal then those within the cafe area. Using a lower gain (dBi) antenna will result in more of a doughnut shaped signal pattern which gives better vertical coverage bringing the signal close to the ground where patrons are sitting with their WiFi devices.
wifi_cafe.jpg

Feb 192014
 

The Ubiquiti UAPs (indoor and outdoor) will mesh automatically if they all share the same SSID (and of course have to be on the same IP subnet).    To set the best path:  You have to do that manually in the UniFi management software

In resonse to customer question:

Our testing was excellent for the Ubiquiti OutdoorAPs. We’re finalizing our proposal and will be purchasing more of them from you. My only question is how to make them mesh automatically for best path? I only see how look and see manually which is best path and them connect them. (Using the UniFi management software).

 Posted by at 11:48 am Ubiquiti Gear Tagged with:  No Responses »
Feb 152014
 

Assembly instructions for the A24 Grid Parablic antenna

 Posted by at 1:57 pm Antennas No Responses »
Feb 142014
 

Summary of 5 major players in the backhaul market along with the premium point to point solutions that they have to offer:

1. Redline Communications offers radio platforms operating between 3.5 to 38 GHz. They support multiple inputs and outputs along with enhanced radio technology to provide the leading throughput in the industry.

The Technology:

One of the point to point solutions offered by Redline is the AN 80i. It uses enhanced IEEE 802.16 radio technology to deliver high data rate and high throughput along with the lowest latency in the industry. It works in the license free 5 GHz band and its radio platform can be configured to provide point to point as well as point to multipoint access between users and networks.

Benefits of AN 80i for Internet Service Providers:

  • It offers a high throughput of 90 Mbps Ethernet PTP.
  • It has exceptional long range capabilities.
  • It possesses lowest in industry end to end latency.
  • Channel size and speed selections are software controlled.
  • Built in quality of service controls to prioritize traffic groups.
  • TDD or time-division duplex transmission.

2. SAF Tehnika is known for providing technology that is usable by public as well as private sector networks. Its technologies are perfect for data as well as voice communications. Its technology gets the credit of being a very flexible because it can be configured in a number of point to point topologies and schemes.

The Technology:  SAF Freemile 24 FODU is the hallmark of SAF Tehnika point to point wireless radio communication. It is a license free ISM band radio that works on 24 GHz for packet data and voice transmission. It is known for its high availability, interference free operation, carrier grade duplex facility without any licensing cost along with easy and quick installation which is a traditional ISM radio feature. The users have a trouble free experience due to the immensely friendly web browser management interface and simple installation process.

Several features offered by Freemile 24 FODU which provide a good reason for users to buy it are:

  • 100Mbps Full Duplex Ethernet
  • Low interference compared to 2.4 GHz and 5.8GHz links.
  • Hitless Modulation Switching technology that ensures the availability of signal even in adverse weather circumstances.
  • Radio polarisation sensor that enables easy installation.
  • It comes along with RF spectrum analyzer.

3. Radwin has introduced a license free point to point architecture by the name of WinLink series that provides high data rate and high throughput carrier services to ISPs for multiple end users from only a single hub site. It is a range of telco-grade products that give great performance at a reasonable price.

The Technology:  The Winlink 1000 point to point radio link combines Ethernet and TDM into a single platform with speed delivering capacity of up to 22 Mbps. The radios used have the latest technologies and vast networking capabilities along with extremely easy installation that reduces its operating costs. With low capital expenditure and low operating expenditure, WInLink 1000 has been able to provide huge possibilities of expansion while at the same time maintaining the profits.

Customer benefits offered by Radwin WinLink 1000 point to point radio:

  • Delivering video, voice and data over one platform thereby cutting access costs.
  • Saving leased lines charges. 
  • Fast deployment with no license costs that increase affordability.
  • Heavy reliability and availability due to robust link redundancy and air interface protocol.

4. Performant Networks provides pay license as well as license free wireless links for the real world conditions that concern the outdoor wireless networks. Its R-FLO technology optimises network paths over fibre links to achieve resilience and Quality of Service to mixed as well as completely wireless technologies.

The Technology:  R-FLO is a result of a number of patented technologies. Its aim is to provide Wireless Internet Service Providers a telecom grade technology that will level the playfield. It targets minimising labour and maximising the output from capital invested while at the same time providing such quality of service that boosts revenue.

R-FLO is beneficial for outdoor point to point wireless where performance is largely affected by signal fade or drop. It can monitor the capacity of every link as well as carry out real time package transmission which enables it to groom the traffic and maintain the Quality
of Service without the need of a “link down†signal to become aware of such a situation.

Reasons to subscribe to R-FLO by Performant Networks:

  • Assurance of performance by combination of carrier grade capabilities and ease of use.
  • Hardware optimised for use by tier-one ISPs. 
  • Link degradation, bandwidth adjusting and back up paths activation capability.
  • Dynamic supervision and dynamic configuration capability.

5. Ubiquiti Airfiber-5 is a 5GHz point to point radio gear. Its compact housing gives it an excellent form factor and it promises a high throughput of up to 1Gbps over license free links.

The technology of Airfiber-5 is based on an efficient use of the 5 GHz band. It features Power Envelope Tracking Technology that is the leader in markets these days along with a 1 MHz resolution for centre channel. Airfiber-5 can continuously and accurately keep
a control on transmit power relative to the band edge thereby giving you the freedom to choose the part of the band that has the least interference. xRT feature of a patent pending technology makes use of the multi channel coding scheme to upgrade the performance of the transceiver thereby maximising your spectrum utilisation and link budget. Its links can reach over 100 Km.

Summary of features of Airfiber-5:

  • Unique sliding clamp design that allows you to assemble mounting hardware prior to installation.
  • Efficient use of 5 GHz band due to Power envelope tracking technology as mentioned above.
  • Superior Processing due to the use of the proprietary INVICTUS core communications processing engine whose power, efficiency and speed amplifies its performance.
  • Availability of two models viz. Airfiber-5 and Airfiber-5U for using mid and high bands frequencies.
Feb 142014
 
  1. Speed:  4G is capable of providing down speed of 0.4 to 50 Mbps and an up speed of 0.2 to 6 Mbps while satellite internet promises down speed of 0.5 to 1 Mbps and up speed of less than 1 Mbps.
  2. Equipment:   With a 4G connection you only need a USB dongle to get access to internet where as a lot of equipment is required to get satellite reception. Hence, 4G is convenient to use and requires less paraphernalia compared to satellite internet.
  3. Weather effects:  Satellite reception is highly affected by weather disturbances at the antenna end while 4G remains unfazed by weather.
  4. Cost:  Satellite internet is much more expensive to install and use than 4G primarily because of the entire hardware setup that satellite internet demands.

Conclusion:  Satellite internet is prohibitively expensive for a private user when compared to 4G and the speed is also nothing
much to write home about. It shall be resorted to only at places where the service provider has no network and hence 4G is unavailable.

Feb 132014
 

I was able to get the awus036 to work with ms internet sharing and networking, but the problem is that it only lasts for a period of time before it looses its configuration and then I have to run the network wizard again. A real pain.

Using the R-36 seems to be the best way however, I still have the same problem with it. Some wifi signals connect and work, however most although also show "connected" in the status window, they do not have a default gateway address and no internet? Are there any tweaks I can do to correct this that you know of? If I use the awus036 by itself, these wifi signals connect and have internet connectivity.

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