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Motorola Releases New Symphony™ Digital Radio Chipset Offering Dramatic Improvement in Reception and Performance
Christmas 2003 Radios Will
Receive More Stations and Sound Notably Better
Fans
of AM/FM radio wanting to enjoy improved sound need not pay for satellite
digital radio or wait for the introduction of land-based digital radio
broadcasts. In a move that has significant repercussions for the digital radio
industry, Motorola’s Semiconductor Products Sector has
developed a new digital radio technology that enhances sound quality and
improves signal reception for existing AM and FM analog broadcasts.
Designed for home and automotive stereo
systems, Motorola’s Symphony™ Digital Radio Chipset implements this
new technology. Its benefits to listeners are numerous: less static, fading,
pops and hisses; automatic tuning, so that adjacent stations won’t
interfere with each other; extended listening range from existing signals; and
overall improved audio clarity and volume. The bottom line: listeners can hear
more stations, whether at home or on the road, tune to more remote stations with
greater ease and enjoy higher quality sound.
Unlike other digital radio offerings, the
Symphony Digital Radio Chipset does not require broadcasters to buy new digital
broadcast equipment. Neither does it require consumers to pay a monthly
subscription fee like those charged by satellite services because it operates on
traditional AM/FM analog
broadcasts.
"Motorola's Symphony Digital Radio
combines all of Motorola's traditional strengths in semiconductors,
communications, and radios," says Jim Turley, semiconductor industry analyst.
"It takes familiar, age-old analog car radio and catapults it into a new age.
Now humble car radios will compare favorably with satellite radio, delivering
more stations, better sound, and less interference -- at almost no cost. It's
even upgradeable through software changes. When Symphony-enabled radios hit the
market at the end of 2003, they'll definitely be on my Christmas
list."
Symphony Digital Radio technology,
usable anywhere in the radio spectrum, is being applied initially in radio
receivers tuning analog AM and FM signals. Impressed by the superior audio
quality in tests against high-end analog sound systems, several consumer
electronics manufacturers plan to introduce radios based on Symphony Digital
Radio in 2003.
“In our quest to bring
music lovers an ever-improved listening experience, we are always looking for
new technologies that will help us advance sound quality and signal reception
performance,” said Hyundai Autonet president J. J. Yoon. “Symphony
Digital Radio is truly a breakthrough technology for the radio industry much as
the CD was for the recording
industry.”
Digital radio is a nascent and
growing market. Today, there are an estimated 800 million analog radios in cars
and alarm clocks, boom boxes and PCs throughout the United States. Two types of
digital radio, satellite and land-based, have focused on transmitting digital
formatted signals to radios equipped with digital receivers. Symphony Digital
Radio allows listeners to listen to the stations broadcasting today, without
changes at the transmitter. Overall, Allied Business Intelligence predicts that
shipments of digital radio receivers in the United States will increase from
650,000 units in 2002 to more than 33 million units in 2007.
“Motorola’s extensive experience
with digital audio has given us a keen understanding of consumer requirements
and engineering challenges in the audio market,” said Motorola
vice-president Bill Pfaff. “With Symphony Digital Radio, we have built on
that experience and created a product that you have to hear to believe. We
believe this product will change the way people listen to the
radio.”
The Magic Behind Symphony
Digital Radio
The key to Symphony Digital
Radio’s performance leap is through frequency tuning: by software instead
of the traditional analog means. Designed from the 24-bit DSP Symphony Digital
Audio architecture, Symphony Digital Radio uses software algorithms to tune,
filter and improve the signal using methods that are impossible to implement via
traditional analog circuits. One can simply download new software to incorporate
new radio features and improvements.
Motorola’s Symphony Digital Audio has a
long history of audio innovation and improvements in a variety of sound systems
from music creation, mastering, commercial theatre surround-sound systems, to
home entertainment systems, to digital audio players such as MP3, CDs and DVDs.
The Symphony Digital Radio chipset can be used in a variety of radio models,
from the feature-rich high-end systems to entry-level lower-feature
versions.
Benefits
Include:
- Range Extension FM
Demodulator—The FM demodulator algorithm used in Symphony Digital
Radio, which separates the FM signal from the carrier, provides superior range
extension and improved Signal-to-Noise Ratio (SNR) under weak signal conditions
over traditional digital demodulation techniques. In other words, this radio
can pick up weaker signals from a greater distance and still provide sparkling
clear reception. Essentially, the Symphony Digital Radio can find low-level
signals that a standard analog radio cannot.
- Better Adjacent Interference
Suppression—Adjacent radio signals often interfere with each other,
not only because they are close together, but also because traditional tuning
cannot lock onto a signal and hold it under changing atmospheric and terrain
conditions. The Variable Intermediate Frequency Filter algorithm used in
Symphony Digital Radio automatically adjusts itself to both 100KHz and 200KHz
band channel spacing, while dynamically reacting to any changes in the
environment.
- Improved Multipath
Interference Suppression—In environments with mountains, hills, or
tall buildings, radio signals bounce off hard surfaces and are reflected
multiple times onto a receiver’s antenna. These reflections can interfere
with each other and cause buzzing, pops, and sudden dropouts, phenomena
collectively known as multipath interference. The Symphony Channel Effects
Equalizer minimizes the effect of these many reflected signals for single
antenna systems. Additionally, by utilizing two antennas, the radio can make
intelligent decisions about signal conditions on both antennas to form a better
signal with reduced fading.
- Embedded
Radio Data System/Radio Broadcast Data System Demodulation and
Decoding—The Symphony Digital Radio baseband processor contains an
embedded RDS/RBDS demodulator and decoder with error correction for those areas
offering Radio Data System (RDS) information on FM broadcasts. Such broadcasts
typically involve station and program identification as well as traffic
information. Station and program information is used to provide frequency
diversity for improved FM reception. The Symphony Digital Radio chipset can
take advantage of this by performing fast Alternate Frequency switching inside
the chipset, rather than by depending on the much slower system microcontroller
to make such decisions.
- Stereo
Separation—In addition, the Symphony Digital Radio provides excellent
stereo separation, often greater than 40 dB, thus exceeding the performance of
current premium analog radios. The software architecture allows for audio
processing and radio tuning simultaneously on a single processor/software
thread. The baseband and audio processor can now handle dual audio streams. By
using a software approach to digital radio implementation, Motorola is able to
reach exceptional levels of digital radio integration in a smaller, lighter and
far more flexible platform.
- Dual Source
Playback—The Symphony Digital Radio chipset solution can be configured
for single or dual simultaneous source for playback. In a car, this means
separate front and rear-seat audio, either two different radio stations or one
radio and one CD input, for example. In the home, this means that different
family members could use the same receiver to tune to their favorite stations in
different parts of the house. The Symphony’s software architecture allows
for audio processing and radio tuning simultaneously on a single
processor/software thread. The baseband and audio processor can also handle
dual audio streams. By using a software approach to digital radio
implementation, Motorola is able to reach exceptional levels of digital radio
integration in a smaller, lighter and far more flexible platform.
- Improved Flexibility—Radio
manufacturers can develop new features through software programming instead of
waiting for new silicon to be added, thus improving performance without
enlarging the footprint. Manufacturers can tweak radio parameters, turn various
algorithms on or off for experimentation, even develop their own algorithms and
download them into RAM. A rich library of third party algorithms is available
today through Motorola’s Symphony Digital Audio family. The Symphony
platform provides sufficient program and data RAM for radio manufacturers to
differentiate between their own radio models via different down-loadable
features, or to distinguish themselves from other manufacturers by providing
their own radio and audio algorithms.
-
Baseband Audio Processing—The baseband/audio processor also features a
number of Motorola’s well-established “plug and play” audio
post-processing features. Also, the open architecture of the Motorola DSP
platform allows for third-party development of new audio algorithms. This
combination creates a rich library of functions that radio manufacturers can use
to differentiate their products. Some of these features include Bass
Management, Delay Management, volume control, dynamic range compression,
parametric equalization (EQ), graphic EQ, bass/midrange/treble control,
loudness, speaker compensation, Dolby B Noise Reduction, Soundfield Processing,
spectrum analysis and level display.
-
Baseband Audio Decoding—The baseband/audio processor provides embedded
multi-channel decoding of 5.1, or six-channel decoding, Dolby Digital from DVD
sources, as well as support for Dolby ProLogic II and DTS Neo:6 in order to
create multi-channel surround-sound effects from stereo sources.
Technical
Features:
The heart of the Symphony Digital
Radio system is the baseband/audio processor. All baseband radio and audio
processing is performed on this single chip rather than a series of chips.
Highly integrated with advanced features, the baseband/audio processor reduces
space and cost while providing a number of significant functions to enhance
performance:
- One or two RF front-end chips
with AM, FM and Weatherband tuning capability (200 KHz to 165
MHz)
- An all-digital DSP baseband/audio
processor, including several special-purpose DSPs and one general-purpose DSP on
a single piece of silicon
- An IF Sigma-Delta
Analog-to-Digital (A/D) converter integrated with audio A/D and
Digital-to-Analog (D/A) converters to transfer data between the RF front-end and
the DSP back-end
- Digital input ports and
Enhanced Serial Audio Interface (ESAI) to connect external DSPs,
Digital-to-Analog Converters (DACs) and other devices to easily accommodate
additional features
- An on-board 6-channel
Asynchronous Sample Rate Converter (ASRC) for interfacing to external digital
devices, such as a MOST Bus or a DVD player
-
An on-board Sony-Philips Digital Interface Format (SPDIF)
Receiver
The company's Web site address is http://www.motorola.com/.
[Reprinted with kind permission from Motorola]
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