Cordless Phone Extender--What Is It??

[WildBoar]

In the May 2002 edition of Nuts & Volts
(page 59), there is an ad for plans to
build something called a "Cordless Phone
Extender." It's suppose to provide a
range up to 50 miles!!<p>Years ago, I remember you could build or
buy amplifiers that boosted your 3-to-5 watt
CB by as much as 100 watts. Of course,
these CB boosters were not legal. I have
no idea how many people built or bought
these devices.<p>Cell phones get there range through an
incredible network of boosted microwave
antennas, signal switching substations, etc.<p>Does anyone have any idea how this cordless
phone extender might work? If it is something
that can actually be constructed, is it
legal?<p>WildBoar

[keymaker]

In my quest for that I found one 2.4ghz amplifier, 500mw, bastads wanted $50<p>They said there was some type of amplifier that was readily avaiable and close enough to the 900mhz range to work for a cordless 900mhz phone<p>But then you must consider the handset.. Better off building a fixed mobile to base unit if you ask me<p>You dont need 10 watts by your mind

[WildBoar]

Hello keymaker.<p>Some of my thoughts about a amplifier for
a cordless phone that could provide enormous
range, are the same as yours.<p>You wouldn't want a gizmo like that next to
your brain!! Building a mobile base station
would be the only sensible thing to do, as
you said.<p>Thanks for your reply, keymaker.<p>WildBoar

[bobsRAC]

Many cordless phones now operate on spread-spectrum technology. Spread spectrum encodes data with pseudo-noise before transmitting to lower the power per bandwidth, while retaining the overall power. The advantage with respect to range is a digital gain. With the redundant data, a few bits can be dropped without affecting the data. By this technique, signals can be transmitted with lower powers for the range. With complex receivers, signals can be rescued from below the noise floor on a particular band.<p>I haven't read the article, but is it possible they are increasing the digital gain factor?