UMA / GAN conformance testing
an overview or tutorial about the basics of GAN / UMA conformance testing
required to ensure their conformance to the required GAN standards so that they
will operate correctly once in use.
UMA technology is now hitting the market and UMA phones can
be seen in the shops. However UMA technology brings together many systems and it
may not always be easy to implement. As a result UMA / GAN conformance testing
is of paramount importance.
In any development programme of electronic equipment it is
necessary to thoroughly test the product at various stages in the development.
The same is true for UMA / GAN phones. As UMA technology is complicated and
brings a variety of systems together, testing is particularly important at all
stages of the development and production process. Testing of the UMA technology
takes various forms at different stages of the development, and often requires
different types of test equipment, some of which can be particularly
specialised.
- Development testing
- Verification and Validation testing
- Conformance testing
- Production testing
Each of these types of test has its place in the development
of any product, and in this case in the development of UMA / GAN phones.
Development testing
During the development of any product, test equipment is
required to ensure that all the circuitry operates as it should. The test
equipment that will typically be required will include items such as
oscilloscopes, as well as RF measuring equipment including spectrum analyzers,
RF power meters and the like. In addition to this test equipment will be needed
to aid debugging the software. This is likely to include emulators of various
types. Thorough testing is required at this stage as it becomes progressively
more difficult to correct any problems at later stages of the development cycle.
Verification and Validation testing
Once the design of the product has been completed, it will be
necessary to ensure that it meets its requirements the requirements set down in
the development specification, and that it also operates satisfactorily. These
tests need to be performed formally to ensure that the development has been
satisfactorily completed and the UMA technology is correctly operational.
UMA GAN Conformance Testing
In order that a UMA phone may be allowed onto the market
where it will be interfacing to equipment from other manufacturers, it is
necessary to ensure that the UMA phone meets the requirements of the UMA / GAN
standard. To achieve this a number of standard tests or "test cases" are
devised. In this way all handsets are tested and certified to the same tests
which reflect the overall UMA, GAN standard.
The test equipment required for UMA / GAN conformance testing
is often very specialized. It needs to be able to emulate that base station,
access point and network, setting up various scenarios to check that the handset
responds in the correct manner. Some typical scenarios would include call
set-up, handover from one cell to another and handover between the bearer
technologies.
As with GSM, GPRS and EDGE, the UMA / GAN test cases have
been specified by GERAN. To date there are 82 GAN test cases providing a variety
of tests. Of these, 70 are focussed on testing the GAN protocol over the
unlicensed spectrum technologies (W-LAN). However twelve of them require the
presence of a GERAN cell to enable handover (from GAN to GERAN and from GERAN to
GAN) to be tested. This is a particularly important feature as this is where
many of the more difficult problems can occur. In addition to this other tests
are also very important and flag up many problems. These can include end-to-end
data capabilities, audio quality checks or even testing of the more common
mobile applications such as MMS over GAN.
Conformance testing is normally undertaken by an independent
test house. Once successfully completed the handset can be certified for use on
the cellular / UMA, GAN networks..
The UMA / GAN conformance test equipment will also find
applications in the earlier stages of testing of the equipment. During
development it will be needed to check that the protocols are operating
correctly. In addition to this, the UMA / GAN conformance test equipment can be
used to debug the handset. At this stage it will be necessary to not only run
the test cases, but also modify them to run a variety of scenarios during the
overall checking and debugging. Similarly it will be necessary to use the UMA /
GAN conformance test equipment during the formal verification and validation
testing.
Production testing of UMA phones
Once an item is in production, testing needs to be performed
on it to ensure that each item leaving the production line performs correctly.
The testing undertaken at this point in the process is aimed at checking that
the unit is built correctly. As this testing adds no value, but only ensures the
unit is operating correctly. At this stage it is necessary to ensure that no
development tests are undertaken; only those that check the build of the
equipment.
The type of test equipment used for production testing of UMA
phones is quite different to that needed for, say, conformance testing. Tests
need to be performed very quickly, and therefore the test equipment is honed to
ensure that it can undertake a limited number of tests very quickly.
UMA GAN testing overview
Although the amount of testing required for UMA / GAN phones
may appear to be large, and the costs may appear to be high, the penalties for
launching a phone that has problems are far higher. With the costs of recall of
many thousands of units on top of the industry and user perception of causing
problems, it is far more cost effective to ensure the testing of any new product
is fully and correctly accomplished to ensure that any new phone using UMA
technology is correct and properly operational.
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