8dBi LPDA WiMax Antenna and spring U1901 modem

[anon4]

I am interested in using the 8 dBi LPDA antenna to go with my Sprint U1901 modem. In my installation it would be a single outdoor antenna (I'm in a very strong signal area but need to get the antenna outdoors for better speed/performance). My question: Is the location of the USB modem critical to performance? I currently have my USB modem sitting on a shelf and it gets good signal strength (-67 db and CINR of 27). However, I discovered my download speeds double and my ping times are reduced by 50% if I move the modem outdoors. Would I need to locate the USB stick in a similar location indoors, or does it matter? (i.e. can it sit on the floor in a corner of the room where it may not have nearly as strong of a signal?) It makes a difference in how long of a COAX run I need to order. If it is not location critical, I can get away with a 10' coax run. Otherwise I will need 20 feet.
Thanks in advance.

[thuor]

Once you mount an antenna outdoors it really doesn’t matter to a large extent where you place the USB modem indoors. This is because the primary antenna is not located outdoors. So you are right you would want to minimize the length of your coaxial cable to save of cost (LMR-400 low loss cable is pricey) as well as reduce cable losses which increase the longer the cable.

However notice I said doesn’t matter much. The reason I say this is because the U1901 and indeed any other modem really has two internal antennas. If you use one outdoor antenna then you are still using the 2nd internal antenna of the USB modem. While this 2nd antenna is not as critical as the primary it would still be nice to give it access to a good enough signal. If you however use two outdoor antennas instead of one then it truly doesn’t matter where you put the USB modem since the internal antennas in the USB modem would be bypassed in lieu of the external outdoor antennas.

In fact most people using a wimax router such as: http://www.rfwel.com/shop/CradlePoin...-N-Router.html do this very thing where they place the modem/router wherever is most convenient since the 802.11n wifi network it creates can get to most parts of the house.

Incidentally why are you looking at the 8dBi LPDA antenna for the U1901? This antenna is a 3G/4G antenna but the U1901 only supports 4G in which case you would probably get better performance with our 18dBi panel antenna which is the most popular antenna we carry for 4G: http://www.rfwel.com/shop/2.5-2.7GHz...l-Antenna.html. Remember dB is a logarithmic scale so there's a BIG difference between 8dBi and 18dBi. The 18dBi is actually cheaper than the 8dBi LPDA.

Finally don’t forget about lightning protection which is strongly recommended any time you are mounting an antenna indoors and running cable indoors.

Hope this helps. Let me know if you have additional questions/clarifications.