ZigBee Gateway/Repeater Antenna Replacement

nherc

We just ordered a couple of the optional 3db ZigBee Antennas from AMX (I had someone else order) and I JUST found out about the outrageous prices AMX is charging for them. Over $400 retail for the 3db one and slightly less for th 5db one (for some odd reason the one with more range costs less).

I mean an extra ZigBee Repeater itself costs less than an antenna upgrade?

Does anyone know the lug/screw type/size of the f-connector on the ZigBee units so I can find a third-party higher gain antenna that will fit correctly? These things are available everywhere due to the proliferation of WAPs and wireless everything now-a-days.

Cheers!

vining

It's an SMA connector but why the high gain antennae? The range on these things are pretty darn good.

nherc

We're just on the edge of needing a repeater on a job with a single gateway and we'd like to limit our troubleshooting/points of failure and pulling another cable. With a little more range we should be A-okay.

Theoretically, you should be able to almost double the range with a $20.00 5.5db Omni Antenna.

Oh, and the connector is SMA, (thanks!), but I think its Reverse Polarity as well. So, it's a RP-SMA.

I'll let you know what I get and how it works out.

vining

Now my brains a little foggy but with those hi gain antennaes do the antennaes give you both tranmission gain or just reception gain. My thinking is that it only increases reception gain but I could be wrong. I would think to increase trasnmission range you have to actually increase transmitter power or focus the power in a particular direction with a directional antennae. If that's is truly the case what does a hi gain antennae really do for you on bi-directional communications transceivers?

REBUILD_EVENT

vining wrote:

Now my brains a little foggy but with those hi gain antennaes do the antennaes give you both tranmission gain or just reception gain. My thinking is that it only increases reception gain but I could be wrong. I would think to increase trasnmission range you have to actually increase transmitter power or focus the power in a particular direction with a directional antennae. If that's is truly the case what does a hi gain antennae really do for you on bi-directional communications transceivers?

if I remember correctly my wireless communication lessons. an antenna Gain ALWAYS is in both direction. the equation was (Power of the Transmitter)*(Sender Gain)*(Transmitter Gain) or something. so you can improve the antenna just on one side. as I do, when I connect to the unsecure Wireless connection of the neighbour to use his broadband internet. I just get an Antenna with more Gain, as I cant change the neighbours antenna

vining

Here's a link on the topic. If I understand this correctly the article states that for an antennae to increase transmission gain it indeed has to focus power in a more horizontal plane which is fine if you not trying to transmit to or receive from areas above or below the device w/ the hi-gain antennae. In most application this may be ideal to take the waisted energy that would otherwise radiate up or down and focus it to radiate horizonally. In a home however it's usually desirable and a requirement to connect from areas above and/or below and use of hi-gain antennaes might actually have unwanted or opposite results.

Now if the antennae focuses the power more horizonatlly hows does that affect the way the antennae recevices signals from areas above or below? I would think that would be decreased as well.

http://www.marcspages.co.uk/tech/antgain.htm