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ScoopTeam - User manual - Draft 0002
Linear coding
Application
music, transmission media with very high capacity and reliability.
The linear coding is in fact the absence of coding/compression, the audio data are transmitted without
information loss and with no bit rate reduction. Obviously this implies a very high bit rate; therefore
linear coding is only usable over an IP network, and with a very high bandwidth and a very good quality
of service, such as a local area network or a high reliability private WAN.
The coding features a sampling frequency of 48 kHz and three variations L16, L20 and L24 for a sample
resolution of respectively 16 bits, 20 bits, or 24 bits for the transmitted audio. With each variation it is
possible to select a mono or dual mono channel mode.
The linear coding is only available for IP networks.
It is not recommended on mobile IP networks due to the required bit rate and the poor quality of
service expected from a mobile network.
2.2.4. Mobile voice and HD voice (
NYA
)
Application: telephony and commentaries, mobile coordination. Moderate latency.
When the unit includes the mobile option, the mobile voice channel can be used for the Coordination
channel.
The standard algorithm used in the network is GSM or AMR. These algorithms are exclusively used for
speech transmission over mobile telephone networks, with a 300 to 3400 Hz audio bandwidth.
Whenever needed, gateways perform transcoding in order to interface with fixed PSTN, ISDN and IP
networks.
When the mobile network supports the so called “HD Voice” service, the AMR-WB coding (standardised
as G722.2 by the ITU-T) is used between compatible mobile terminals, and provides speech transmission
with a 50-7000 Hz bandwidth. ScoopTeam automatically implements this algorithm in mobile voice
mode every time it is possible, and automatically falls back to standard voice coding if not (when the
network does not support HD voice, or the remote terminal is not compatible).
