Home |
Search |
Today's Posts |
|
#1
|
|||
|
|||
Long Range Wireless Network
I am trying to establish a wireless network for Internet Access, Video
Conferencing and Intranet Applications, I though to use either a 2.4GHz Sector or Omni Directional Antenna would do the job but I can find any product that goes as far the distance I am trying to cover (a radius of 20Km). My idea is to use a powerful radio with the Antenna monted on a tall mast at the location of the internet feed (via VSAT), this location is idea for LOS at the other locations. Does anybody has experience/advise with this ? |
#2
|
|||
|
|||
Long Range Wireless Network
On Wed, 10 Oct 2007 07:16:24 -0000, wrote:
I am trying to establish a wireless network for Internet Access, Video Conferencing and Intranet Applications, I though to use either a 2.4GHz Sector or Omni Directional Antenna would do the job but I can find any product that goes as far the distance I am trying to cover (a radius of 20Km). My idea is to use a powerful radio with the Antenna monted on a tall mast at the location of the internet feed (via VSAT), this location is idea for LOS at the other locations. for such application you will need on both sides approx. 80cm (offset used Sat) dish with properly mounted a proper feed to it; visual line w/o obstacles in-between is a must ! get some clues: http://www.seattlewireless.net/DirectionalParabolic -- Regards , SPAJKY ® mail addr. @ my site @ http://www.spajky.vze.com 5y - "Tualatin OC-ed / BX-Slot1 / inaudible setup!" |
#4
|
|||
|
|||
Long Range Wireless Network
|
#5
|
|||
|
|||
Long Range Wireless Network
Bruce in Alaska wrote:
In article , (Geoffrey S. Mendelson) wrote: 20 KM, is an awfully long range for a MESH network anyway. snip 20Km isn't at all a long distance, snip I think the O.P.'s problem is regulatory issues regarding EIRP in his country preventing him from using hi-gain antennas. Regards, Michael |
#6
|
|||
|
|||
Long Range Wireless Network
|
#7
|
|||
|
|||
Long Range Wireless Network
On Oct 11, 4:50 am, Fred McKenzie wrote:
In article .com, wrote: I am trying to establish awirelessnetworkfor Internet Access, Video Conferencing and Intranet Applications, I though to use either a 2.4GHz Sector or Omni Directional Antenna would do the job but I can find any product that goes as far the distance I am trying to cover (a radius of 20Km). My idea is to use a powerful radio with the Antenna monted on a tall mast at the location of the internet feed (via VSAT), this location is idea for LOS at the other locations. Does anybody has experience/advise with this ? As I understand the problem, thenetworkwould cover an area with a 20Km RADIUS. You include a reference to an omnidirectional antenna and a "powerful" radio, with the base station antenna mounted sufficiently high to be line-of-sight from the end-users. My thought is that you are a bit naive, describing a one-way system similar to a Television or FM Broadcast Station. There are existing systems used for providing community internet access, and I don't think that is how they work! While I'm not familiar with the community systems, there are technical problems with your proposal. For one, it is a two-way system. If high power is required at either end, it is required at both ends. Even with a high gain antenna at the remote end, the gain works on both transmitting and receiving. For another, by using a single base station site to cover such a wide area, the base station receiver will be exposed to various noise sources over that entire area. The total interference from these sources will reduce data rates for all users' transmissions toward the base station. Perhaps Geoff's MESHNetworkor Bruce's WiFiNetworkwould be a good approach, but breaking the coverage area down into a more manageable size and using multiple sites. Fred K4DII Thanks for the responces, the proposal as rightly said is no different from Wireless networks deployed by ISP in small communities. All I need is pointers to hardware that can be used to archive this winthin legal limits. The WiFi Solution seems to me more resonable as braking the area into chucks means that some sites would be dependent on others |
#8
|
|||
|
|||
Long Range Wireless Network
|
#9
|
|||
|
|||
Long Range Wireless Network
On Oct 12, 11:55 am, Fred McKenzie wrote:
In article . com, wrote: Thanks for the responces, the proposal as rightly said is no different from Wireless networks deployed by ISP in small communities. I think you are zeroing-in on a plan that will work. My point is that a 20Km radius is NOT a small community. While the VSAT link may have sufficient bandwidth, your wireless distribution system may not. It would help reduce the load by using a higher bandwidth method such as fiber, to interconnect the various local wireless base stations to the VSAT terminal, rather than using the wireless systems themselves for inter-site distribution. Remember that a wireless system's bandwidth is divided among all the users. As more users access the network at any one time, the slower will be the response. Fred K4DII Just to chime in on this topic, I think some incorrect information was passed along regarding legality of transmission power - the FCC does in fact limit unlicensed maximum transmission wattage on the 2.4Ghz range, however the use of high gain antennas is NOT illegal. You can use extremely high gain directional antennas to achieve links over a 20+ mile LOS link, and still be within legal limits for unlicensed operation. Think of it as using as talking thru a funnel - all it is doing is using that same power more efficiently and more focused. Now if you are talking about running the signal thru and actual signal amplifier, then yes, that would be illegal. 2 cents |
#10
|
|||
|
|||
Long Range Wireless Network
wrote:
Just to chime in on this topic, I think some incorrect information was passed along regarding legality of transmission power - the FCC does in fact limit unlicensed maximum transmission wattage on the 2.4Ghz range, however the use of high gain antennas is NOT illegal. You can use extremely high gain directional antennas to achieve links over a 20+ mile LOS link, and still be within legal limits for unlicensed operation. Think of it as using as talking thru a funnel - all it is doing is using that same power more efficiently and more focused. Now if you are talking about running the signal thru and actual signal amplifier, then yes, that would be illegal. Unfortunately, this is also incorrect. The limit is for EIRP. The more focused the beam, the higher the EIRP. The exact limit the U.S. is 1 watt EIRP for mobile devices and 4 watts EIRP for fixed (point to point) links. That's a combination of transmiter power plus antenna gain plus feed line loss. Ham radio is limited to transmitter output power, which is quite different. It could be worse, the limit here is 100mW EIRP. Geoff. -- Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM IL Voice: (07)-7424-1667 U.S. Voice: 1-215-821-1838 Visit my 'blog at http://geoffstechno.livejournal.com/ |
Reply |
|
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Long range rural wireless high speed data options... | Homebrew | |||
Securty missalany, wireless network DX ... | Shortwave | |||
problem with wireless bridge in workshop to home network | General | |||
Computer Wireless Network Interferance | Shortwave | |||
Wireless network | Antenna |