What are the facts about cellular amplifier performance?
(information from Wilson Electronics' website)
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Understanding amplifier performance is extremely important when researching different
amplifier products on the market. At Wilson, we stand by our claim that our amplifiers perform
better than any of our competition because we design and engineer them to work better than
our competitors. After testing by our own engineering staff, we have an outside, accredited,
independent cellular industry testing laboratory verify our test results with their own testing.
There are three major performance specifications that form the basis for a performance
comparison: The first performance specification is receiver sensitivity, which is the ability of the
amplifier receiver to pick up a weak signal from a Carrier’s cell site. Testing must be done with
the correct criteria and methodology using equipment specifically made for testing cell phones.
Wilson has the ability to do this type of testing in our engineering facility where we have a cell
site simulator and a double electrically insulated radio frequency (RF) enclosure.
Once we test internally, then we have our testing results independently verified by an outside
testing laboratory that performs tests for the major carriers and cellular manufacturers.
The performance standard we test against is the CDMA performance standard. This is the
most complete and preferred testing standard because it tests for the weakest signal that will
still give a usable, quality voice and data output from the test device with a 0.5% frame error rate
(FER) or less. In other words, an amplifier with better receiver sensitivity can detect a weaker
signal, which allows the cell site to communicate with the cell phone at a greater distance.
Wilson outperforms all the competition on the CDMA performance standard.
By using the CDMA performance standard as a baseline, a true comparison can be made
between cell phone and amplifier performance. A typical cell phone must have a sensitivity of
-104 dBm or better. The higher the dBm number a tested device gets, the weaker a signal that it
can receive and pass the test. (For example, a -110 dBm level can pick up a signal 6 dB weaker
than -104 dBm.) A 6 dB improvement in receiver sensitivity will allow an amplifier to pick up the
same signal at twice the distance from the cell site. Using the same CDMA performance testing
standard, the Wilson Dual-Band Direct Connection Amplifier on 1900 MHZ has a -109.3 dBm
receiver sensitivity, while the Digital Antenna DA4000 Amplifier has a sensitivity of only -104.2
dBm. That means the Wilson amplifier can pick up a signal 79% farther than the Digital
amplifier on flat terrain.
Misleading sensitivity claims are used by our competition, which is why we test their products
against ours. Digital Antenna claims their direct connect amplifier’s receiver has a sensitivity of
-123 dBm. This higher number is meaningless because it gets higher and higher by reducing
the received bandwidth during testing. The measurement must be done at the cell system
bandwidth as the established benchmark and then be compared with other amplifiers using the
same comparison criteria on the same CDMA cell site test set. This is the methodology we use
at Wilson and the standard used by all other accredited comparison tests.
The second performance specification is the Transmit Test, which includes open loop power,
closed loop power, minimum and maximum power tests for CDMA to assure the amplifier
meets CDMA specifications and will not harm the Carrier’s cell site. Some amplifiers such as
the Richardson Electronics B800-1900-1 do not even meet the minimum power requirements
for the cell phone being tested (see test results, click here).
The third performance specification is to test for quality control and assurance. Wilson uses
sophisticated automatic computer testing stations that run as many as 40 different operational
tests on each amplifier before it is shipped out to our product dealers. This assures
consistency that each amplifier has been tested for performance and meets our quality control
criteria before it is shipped out.
Our approach at Wilson is to follow these three performance specifications in determining the
performance of our amplifiers. We publish the test results and make the comparisons against
our competition available for product dealers and customers to make an informed decision
about what product to purchase. We stand by the testing results that show Wilson products
outperform the competition!