The Universal Mobile Telecommunications System (UMTS) is a third generation mobile cellular system for networks based on the GSM standard. Because of this systems prominence, and because of wireless users’ network demand, UMTS testing is necessary. UMTS uses wideband code division multiple access (W-CDMA) radio access technology to offer greater spectral efficiency and bandwidth to mobile network operators. Unlike EDGE (IMT Single-Carrier, based on GSM) and CDMA2000 (IMT Multi-Carrier), UMTS requires new base stations and new frequency allocations.
How to test UMTS
The process for conformance testing for UMTS is well defined and operates smoothly. The conformance test approval process is run by the industry itself and is bascially self regulating. Because of the fact that all phone designs have to pass the conformance test process, it means that the number of problems discovered with phones is very low. Once the manufacturer is satisfied that the test operates satisfactorily he provides it to an independent validation organization that will test it and for conformance with the original test case. Assuming that the test case satisfactorily passes this process then it is presented to an industry body for certification. Once it has achieved this status then it can then be used for formal handset testing and certification.
3GPP has the control over this testing process. However changes are handled by a group known as the T1 group for UMTS. The validation and approval of the implemented test cases is then handled by the GCF (Global Certification Forum).
“As might be expected, experience gained on GSM has been reflected into improvements for the new third generation UMTS system. One of the main changes is that the protocol test cases, are initially written in prose and then converted into TTCN (Tree and Tabular Combined Notation) to be made available to the industry. This language enables the test cases to be compiled into a format that can be run directly on the target test equipment. This approach saves time for the industry as a whole and reduces costs because generating the test cases is far easier to achieve. The main advantage is that it gives far more consistency across the industry as tests are no longer open to the same level of interpretation that they were before. This also saves time in the validation process.”
To test a new handset, the manufacturer usually employs a qualified test house who will possess a variety of different test systems. They will then run the required certified test cases and be able to present a case for a handset being suitable for use on the available networks. [1]
So why all this testing? Well, today’s modern mobile phone is a highly complex electronic system made up from a variety of diverse sub-systems, all of which must work seamlessly together. Mix that with the fact that today’s users have very high expectations which set tough demands on manufacturers as they introduce third generation technology. While yes, today’s phones are built to have stellar performance and behavior on the network, the only way to know for sure is with testing, therefore, making testing an important part of any mobile phone’s life cycle, from development through to manufacturing and beyond.
[1] Radio-Electronics.com, GSM/UMTS Conformance Testing, http://www.radio-electronics.com/info/cellulartelecomms/cellular-testing/gsm-umts-conformance-test.php
http://www.radio-electronics.com/info/cellulartelecomms/cellular-testing/gsm-umts-conformance-test.php