1. Modeling of RF in W-CDMA with SystemView
RENE: Wireless Cellular Radio Srikrishna Bhashyam, Sridhar Rajagopal, Kanu Chadha, Dinesh Rajan, Bryan Jones, Yuanbin Guo, Ahmad Khoshnevis, Frank Livingston, Charles Camp, Behnaam Aazhang, Joseph Cavallaro
RENE Receiver
Next Generation Cellular System
Multimedia capabilities
Multirate services
Guaranteed Quality of service
Higher Data Rates: 2 Mbps, 384 Kbps, 128 Kbps.
antenna
Cellular phone
Basestation
(Cellular tower)
- or a -
and are…
Come from a
Channel estimator
Web pages
Videophone calls
and 
Web page
Sent via RF (radio
waves) over the air
RF receiver / demodulator
Detector
Decoder
Videophone call
Algorithm
Implementation
Theory
Practice
Then, take these algorithms (theory)…
…to implementation in a prototype
basestation (practice)
Channel Effects
Multiple Users share spectrum
Multiple Access Interference
Multipath Fading
Additive White Gaussian Noise
Multiprocessor Basestation Implementation
2.4 GHz ISM hardware
DSP + FPGA
Performs channel estimation
Performs detection
Performs decoding
Performs RF reception
antenna
The Wireless Channel
Direct
Reflections
noise + interference
User 1
User 2
Base-station
The Sundance board contains 2 DSPs and 2 FPGAs.
Multiprocessor Simulations
The channel estimator and detector have been implemented on this platform. Measurements show a 2 DSP solution to be faster than a single DSP solution. Projects demonstrate using both DSPs and FPGAs provides even greater performance.
Larger values are worse (slower) 5 10 15 20 25 30 35 -6 -5 -4 -3 -2
Execution time (in seconds)
Users
Single DSP implementation
2 DSP implementation
Target data rate Kbps/user
2 DSPs + 2 FPGAs
Modeling of RF in W-CDMA with SystemView
-148
-140
-130
-120
-110
1.00e-2
1.00e-1
BER
Path loss in dB
BER vs Path loss in dB
Baseband Simulation
Scheme with RF
-102
Output BW=InFs/N
N: 2~64 --wideband
32~ narrow
Decimation factor
>40MSPS
Future Work
Welkin
>40MSPS
Complete system evaluation on multiple DSPs and RF hardware
Carrier offset and synchronization - multiple users
Mobile handset - low power, fixed point DSP implementation
Integrating physical layer with higher layers
Task partitioning and Parallel architectures for acceleration
Welkin
Complete System with DSP+RF
Distortion True RF modeling (IP3,P1dB, NF…)
Real world Component Specification
Multi-domain Integration ( SystemView + Matlab)
Software Radio design with DDC/DDS