ACCESS Product Manual
29
HQ2 Stereo Default
– This profile offers a stereo stream using
only around 30kb/s. It has the same delay and robustness aspects
as HQ2 default above. The stereo stream created needs to have
correlation between left and right channels (i.e. you can not send
independent programming down each channel).
ULB Default
– This profile is best for challenging IP connections. It
uses a very small bandwidth stream (14 kb/s) and delivers two-way
7KHz mono voice audio. Not useful for music. For more details, see
the algorithms section.
3G
– This mode is optimized for use over 3G wireless networks
like UMTS, EVDO, and HSDPA. Because 3G networks are usually
asymmetrical (they have higher download speeds), this profile
delivers a robust, medium delay mono stream in the upload
direction, and two, independent low delay mono streams in the
reverse direction. These two streams can be useful as separate
program and cueing channels, as an example.
BGAN
– Profile optimized for use over INMARSAT BGAN terminals.
This profile keeps the entire data stream beneath the limit for 32K
streaming service, which is the most economical mode for use on
ACCESS. This mode provides a robust, medium delay mono stream
in the forward direction, and a low delay mono stream in the
reverse direction.
POTS
– Profile used for connections over the modem card directly
to other ACCESS or other Comrex POTS codecs (not through the
internet).
Linear PCM
– Profile used for sending and receiving Stereo
uncompressed audio. Linear PCM requires a large amount of
network bandwidth and is generally not suitable for use on the
public Internet. Usable in LAN environments (wired or wireless) or
with high-speed IP radio links.
FLAC
– This profile uses the Free Lossless Audio Codec algorithm
for stereo send and receive audio. FLAC can conserve network
bandwidth by 30-40% with no loss of audio quality, and only
slightly higher delay (when compared to Linear PCM). FLAC still
requires a much higher network bandwidth than is available on
most public Internet links.
There are several additional factory profiles that use the industry
standard AAC Audio Encoders, including: AAC, AAC-LD, HE-AAC &
AAC-ELD.