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A Modified Non Coherent PN Code Acquisition Scheme. Rethnakaran P Ubi N etics E-Mail: ratna.p@ubinetics.com , ratnu@ieee.org Joint work with P.K.Venkataraghavan PK (Synopsys Inc) and Tapan Ray (Wipro Technologies). Agenda. Acquisition Problem Existing solutions
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A Modified Non Coherent PN Code Acquisition Scheme Rethnakaran P UbiNetics E-Mail: ratna.p@ubinetics.com, ratnu@ieee.org Joint work with P.K.Venkataraghavan PK (Synopsys Inc) and Tapan Ray (Wipro Technologies)
Agenda • Acquisition Problem • Existing solutions • Modified Non-coherent Detection scheme • Performance • Analytical, Simulation results • Summary
DSSS System (Transmitter) • Transmit Signal
DSSS System (Receiver) • Received Signal • Down Converted I-Q
Acquisition Problem • Identify (Detect) the transmitted PN code (Code Phase) from the received (I and Q) signals,
System Model • Receiver Structure
Non Coherent Detection Scheme • Non Coherent Detector Structure • Why Non Coherent? • Unknown Random Phase • Data modulation yet to be removed • Penalty • Compared to Coherent scheme
Modified Non Coherent Scheme • DNC Structure
System Model (Continued) • Post Detection Integration • No Post Detection (L=1) • Matched Filter Based Receiver • PN Sequence used • AWGN • No Fading • DSSS/BPSK • Performance Criteria – ROC • Probability of Detection Vs Probability of False Alarm
Analytical Results (ROC) • False Alarm Probability • Probability of Detection
Summary • New Structure Proposed • Analytical Expressions (ROC) Derived • 2dB SNR Advantage Over Conventional Non Coherent Scheme • Supported by System Level Simulations
Q&A Thank You Rethnakaran P UbiNetics E-Mail: ratna.p@ubinetics.com, ratnu@ieee.org http://ratnu.tripod.com http://www.ubinetics.com