Beamformer Data Characteristic
The Audio Beamformer Data characteristic is used to allow the RVS Server to provide information about beamformers used in the voice session. The Audio Beamformer Data characteristic is optional.
The characteristic UUID shall be set to: TBD
Beamformer Data Characteristic Value
The Beamformer Data Characteristic contains up to 4 fields describing beam data from a beamformer running on the RVS Client as described in below.
Field | Size | Description |
---|---|---|
Beam Data 1 | 5 Octets | Beam 1 data. |
Beam Data 2 | 5 Octets | Beam 2 data. |
Beam Data 3 | 5 Octets | Beam 3 data. |
Beam Data 4 | 5 Octets | Beam 4 data. |
Beam Data Field
The format used for each Beam Data field in the Beamformer Data Characteristic is describes in Table below.
Bits 8 | 16 | 16 |
---|---|---|
Beam Description | Confidence | Signal Noise Ratio |
The Beam Description byte uses the format described in Table below.
Bits 0-3 | Bit 4 | Bit 5 | Bits 6-7 |
---|---|---|---|
Reserved | Selected | Triggered | Angle (0, 90, 270, 360) |
The Confidence value is float between 0-1 that has been converted to an unsigned 16-bit integer. This value represents the confidence level of the keyword detector.
The Signal Noise Ratio is a signed 16-bit integer where 1 unit is equal to .01 SNR.
Client Characteristic Configuration Descriptor
A Client Characteristic Configuration descriptor shall be included in the Beamformer Data characteristic.
Beamformer Data Characteristic Behaviour
If the RVS Server supports the Beamformer Data characteristic, the RVS Server MAY notify on the Beamformer Data Characteristic if the audio session was initiated by a keyword before the Data characteristic is notified on.