Volvo 2011 C70, Руководство пользователя

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10 Audio
Radio functions
10
``
245
HD Radio ൅ ൅ reception (U.S.
models only)
1
Introduction
Display when the radio is receiving an HD Radio
broadcast
HD radio is a brand name registered by the
Ibiquity digital corporation
2
. They are the
developer of a broadcasting technology called
IBOC or In Band On Channel, which refers to
the method of transmitting a digital radio
broadcast signal centered on the same fre-
quency as the AM or FM station's present fre-
quency.
The IBOC system is referred to as a "hybrid"
since it is both analogue and digital. During
hybrid operation, receivers still continue to
receive the analogue (non-digital) signal. HD
radio receivers incorporate both modes of
reception, where the receiver will automatically
switch to the analogue signal if the digital signal
cannot be decoded or is lost by the receiver.
When you have tuned to an HD Radio station,
the
symbol will appear in the audio sys-
tem display.
More information about HD radio and IBOC
can be found on Ibiquity's website,
www.hdradio.com and www.ibiquity.com.
Benefits of digital broadcasting
•
Better sound (FM sounds near CD quality
and AM as analogue FM).
•
Some FM frequencies offer a greater num-
ber of listening choices through “multicast-
ing” (consisting of a frequency's main
channel and any sub-channels that may
also be available on that particular fre-
quency. See also the section "Sub-chan-
nels" below).
•
When receiving a digital signal there is no
multipath disturbance or hisses/pops/
crackling due to outside influences.
How HD broadcasting works
HD Radio works similarly to conventional radio
and broadcasts of this type are available in
many areas of the United States. However,
there are a few key differences:
•
Instead of transmitting one analogue sig-
nal, stations send out a bundled signal –
both analogue and digital.
•
An HD radio receiver can receive both dig-
ital and analogue broadcasts. Depending
on the terrain and location of the vehicle
(which will influence the signal strength),
the receiver will determine which signal to
receive.
Limitations
•
Main channel vs. sub-channels (FM
only)
: The main channel is the only channel
that can receive in hybrid mode (both dig-
ital and analogue). If a frequency has sub-
channels, they are broadcast in digital
mode only. The main FM channel will be
displayed as, for example, 93.9 WNYC
(Volvo uses the symbol > to indicate there
are sub-channels available) The sub-FM
1 HD Radio(TM) technology is manufactured under license from iBiquity Digital Corp. U.S. and Foreign Patents. HD Radio(TM) and the HD and HD Radio logos are proprietary trademarks of iBiquity
Digital Corp. HD Radio(TM) is only available in vehicles not equipped with the optional integrated CD changer.
2
HD Radio (TM) technology is manufactured under license from iBiquity Digital Corp. U.S. and Foreign Patents. HD Radio(TM) and the HD and HD Radio logos are proprietary trademarks of iBiquity
Digital Corp.