TIA-470.120

Description / Abstract: This standard provides acoustic transmission performance requirements for speakerphone equipped analog telephones intended for connection to the Public Switched Telephone Network (PSTN), analog terminal adaptors (ATA) and voice gateways. These requirements should ensure compatibility and satisfactory performance to the user in a high percentage of installations. Test measurement methods reference procedures in IEEE Std 1329 where applicable.

This standard is limited to single housing speakerphones intended for use on a desk, table, or handheld (i.e. cordless handsets) by a single user at a distance of one half meter or closer. These requirements are not intended for multi-user conference speakerphones.

While the procedures may call out specific test points within the requirements, the full range of the requirements take precedence.

LIMITS OF THIS STANDARD FOR PRODUCT EVALUATION

It is recognized that there are many parameters that may influence the performance of speakerphone devices including:

1. The distance between the user and the speakerphone device

2. Users with a variety of talker levels

3. The level and type of environmental noise

4. Non-linear processing included in the speakerphone device design (e.g., AGC, AEC)

This standard establishes the performance requirements for speakerphones with the following limitations:

1. A single test position is used to simulate the distance between the user and speakerphone.

2. The speakerphone is tested without environmental noise present.

3. Testing is performed without consideration for any effects of non-linear processing, although such non-linear processing may be present.

Subjective testing may provide additional information regarding a speakerphone device’s performance. However, the subjective test shall not be a substitution for the objective test nor a condition to pass the standard.

ENVIRONMENTAL

This standard does not contain environmental requirements. Environmental requirements can be found in ANSI/TIA-571-C.

SAFETY

This standard does not contain safety requirements.