BOARDCOM BCM3118B Qamlink dvb/davic receiver Datasheet

BCM3118B
PRODUCT
Brief
®
BCM3118B
B C M 3 1 1 8 B
Q A M L I N K ® D V B / D AV I C
F E AT U R E S
S U M M A R Y
O F
RECEIVER
B E N E F I T S
• Downstream QAM receiver for international
• Fully integrated solution enables less-complex,
• Integrated QAMLink receiver with Forward Error
• Significantly increases channel capacity
• Variable data rates enable systems to adapt to
applications
Correction (FEC)
• 1-7 MBaud variable symbol rate receiver
• Supports variable channelization
• Supports 4, 16, 32, 64, 128 and 256-QAM
• Digital demodulator, Nyquist filters, tracking loops,
and 20-tap adaptive decision feedback equalizer
• Digital derotator for wideband carrier phase tracking
• DVB/DAVIC-compliant FEC decoder
• Reed-Solomon (N,K) = 204,188: t=8
• Convolutional detinterleaver, I=1-12 with internal
RAM, I=204 with external RAM
low-cost cable modems and cable-TV set-top boxes
channels encoded at different data rates
• Integrated A/D converter reduces system
manufacturing costs and complexity
• A universal chip solution that supports DVB, DAVIC,
ITU-T J.83/Annex A and Annex C, IEEE 802.14-based
systems
• Digital adaptive equalizers ensure robust performance
in the presence of multipath reflections
• I C or SPI-compatible microcontroller interface
• Integrated 10-bit analog-to-digital converter
• On-chip generation of all clock and control signals
• JTAG test interface
• 100-pin PQFP Package
2
Interactive Set-Top Box with DOCSIS and Watch and Record Dual Video Channels
Video 1
DOCSIS/EuroDOCSIS 1.1/1.0
Out-of-Band
BCM3250
Advanced
Single-Chip
Set-Top Box
Front End
Video 1
Video Out
PCI
BCM7030
High Definition
Video/Graphics
Subsystem
Video 2
BCM3118B
Audio Out
Video 2
CPU
B C M 3 1 1 8 B
O V E R V I E W
4
Nyquist
α = .13-.15
10
A_IF+/-
A/D
Phase
Recovery
and
8-Tap
FFE
Variable
Rate
Demod
I
ReedSolomon
Decoder
(204, 188)
t=8
12-Tap
DFE
Nyquist
α = .13-.15
PS_DATA
4
LPS_SYNC
LPS_DATA [7:0]
PS_ERR
Q
RAM_CTRL
sin ωn
cos ωn
LPS_CLK
Deinterleaver
RAM
AGC_CTRL
BAUD_CTRL
IF_OSC
Acquisition/Tracking Loops
and Clock Generation
Phase
ROM
JTAG
Tuner
Control
JTAG [3:0]
RF [5:0]
GEN_CTL
The BCM3118B QAMLink DVB/DAVIC Receiver with FEC is
an integrated digital transmission solution for cable modems,
cable-TV set-top boxes and digital microwave radios. Its
bandwidth-efficient feature set expands the existing potential
bandwidth of a standard analog network and provides operators
with reliable, error-free transmission. Optimized for highvolume manufacturing, the BCM3118B is a highly integrated
solution that reduces the system-level chip count, the cost, and
the complexity associated with manufacturing RF receivers.
A single-chip solution, the BCM3118B has a 10-bit A/D
converter, a 256-QAM demodulator with square-root raisedcosine receive filters, an adaptive equalizer with an embedded
phase recovery derotator, acquisition and tracking loops, and a
DVB/DAVIC-compliant Reed-Solomon FEC decoder with
deinterleaver. The demodulator supports QPSK, 16, 32, 64, 128
and 256-QAM formats and adapts to channels encoded at
different data rates up to 56 Mbps. The equalizer in the
BCM3118B achieves transmission performance within 1 dB of
theory over worse-case channels with multipath delays as long as
2.4 microseconds at 5 MBaud or 1.7 microseconds at 7 MBaud
and amplitudes within .5 dB of the desired signals. With this
level of performance, the BCM3118B combats the effects of
channel distortions commonly found in cable-TV systems. The
MBus/SPI
Interface
MICRO [3:0]
BCM3118B has an integrated A/D converter, which eliminates
the costs associated with fine tuning of external components
during high-volume production.
The BCM3118B samples the analog IF waveform being
delivered to BCM3118B by the integrated A/D converter. The
signal is then digitally mixed to baseband and filtered by dual
square-root Nyquist filters. Inter-symbol interference is then
removed by the adaptive decision feedback equalizer. A decision
slicer, which supports constellations up to 256-QAM, formats the
equalized data. The data is then fed into a DVB/DAVICcompliant synchronization block, deinterleaver, Reed-Solomon
FEC, and derandomizer. The final error-corrected output is
delivered in an MPEG-2 transport format.
The BCM3118B can be used as a stand-alone chip or with
Broadcom's BCM3250 for a complete watch and record solution
with EuroDOCSIS. Compliant with the ITU-T J83/Annex A and
Annex C, DVB/DAVIC and the IEEE802.14 cable transmission
standards for QAM downstream, the BCM3118B is a universal
downstream solution for worldwide coaxial cable applications.
Broadcom®, the pulse logo, QAMLink® and Connecting everything® are trademarks of
Broadcom Corporation and/or its subsidiaries in the United States and certain other countries.
All other trademarks are the property of their respective owners.
®
BROADCOM CORPORATION
16215 Alton Parkway, P.O. Box 57013
Irvine, California 92619-7013
© 2003 by BROADCOM CORPORATION. All rights reserved.
3118B-PB05-R-06.13.03
Phone: 949-450-8700
FAX: 949-450-8710
Email: [email protected]
Web: www.broadcom.com
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