> 1.3 | Approval Considerations

> The Siemens GSM modules listed in Section 1.1 have been type approved for use with the Siemens reference equipment described in chapter 8. Regarding audio performance, compliance with the TS 51010-1 specification and GCF recommendations has been certified for the parameters provided by audio mode 1 and audio interface 1. The settings are optimized for the reference handset (type Votronic) connected to the evaluation kit DSB75. To ensure that the reference parameters are always within the limits demanded by the standards they cannot be changed by AT command. Furthermore, the reference parameters are set as factory default.
> If the customer’s application is a mobile device with inbuilt microphone and speaker it needs to be compliant with the TS 51010-1 requirements specified for frequency response, loudness, listener side tone and noise suppression. All measurements shall be done with the mobile device connected to the artificial mouth and the artificial ear test set. Siemens offers assistance in adjusting the internal DSP to ensure that mobile devices with internal microphone and loudspeaker are fully standard compliant. This is achieved by creating a customized audio parameter file which can be downloaded onto each mobile device. The service is available on request, for further information please contact Siemens.
> If the customer’s application connects to an external headset or speakerphone it is not necessary to fulfill the above GSM specifications. Yet, to achieve a high standard of audio quality in the final product and to shorten the time of development Siemens is offering the same audio parameter customization service. For this kind of applications, the focus is on customizing frequency response, echo cancellation and noise reduction parameters according to the properties of the connected peripherals.
> Outside Europe, there may be further international, national or government standards and regulations to be observed for type approval.