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In recent years, wireless smart devices which use radio frequencies are emerging increasingly in all areas of our life. This article presents the influences of radio frequency (RF) output power level on RF electromagnetic field and RF common mode immunity tests of wireless radio equipment.According to the ETSI EN 301 489-17, the RF output power level should be adjusted to the maximum level during the tests. However, the use of RF output power level in daily life may not work at the maximum or fixed level in a wireless device. In order to observe the effects on test results, RF common mode and RF electromagnetic field immunity tests are performed at the maximum RF output power level as stated in the standard and at different RF output power levels as independent from the standard. The results of the measurements are compared with each other at the certain frequencies.

In this article, the differences between the test method of receiver blocking test which exists in new and previous version of ETSI EN 300 328 radio standard have been evaluated. The main differences between the two versions are blocking and communication signal power levels. The communication signal is named as wanted signal mean power from companion device in the related standard.In the previous version, the communication signal power level is determined by the manufacturer, provided that it meets a certain criterion, while it is determined by taking into account the occupied channel bandwidth of the product according to new version. In this manner, the effects of the manufacturer or the test laboratories who perform this test on the test results are eliminated. Two different radio products have been tested in compliance with the previous and new version of EN 300 328 radio standard and the test results have been compared.

EN 55032 defines an open area test site (OATS) for radiated emission testing. There are two alternatives to OATS, which are semi anechoic chamber (SAC) or full anechoic room (FAR). SAC and FAR limit values for radiated emission test are different according to the standard. In this article, the consistency of the SAC and FAR limits are assessed by using comparison noise emitter (CNE). All tests are performed in the same chamber. Ferrite modification is applied to SAC in order to perform tests as a FAR. Thus, the number of variables which can affect the test results is kept at the minimum level. Measurements are performed in the frequency range of 30 MHz to 1 GHz. Measurements for CNE were made in two ways that are the antenna being constant at 1.55 meters and moving between 1 meter and 4 meters. Thereafter, margin levels were compared and the consistency of limit levels for SAC and FAR at the standard was analyzed.