1. Update on the New Developments & Analysis from Hawaii Larry Ruckman & Gary Varner Instrumentation Development Laboratory (ID-Lab) University of Hawaii at Manoa January 31, 2008

2. Agilent Pulse Measurement Two separate BLAB1 ASIC with a common sampling strobe RF split the Agilent pulse with additional cable delay in the 2 nd channel Tune the AC coupling capacitor to create a fairly Gaussian looking signal CH1 CH2

3. Agilent Pulse Fitting Apply Gaussian fit to both functions Measure the time difference between the two fit means => actually a factor sqrt(2) better High timing resolution for a fixed amplitude over a small timing window Gaussian Fit 6.4 psRMS

4. Pulse Fitting Disadvantages Spend a lot of time developing an amplitude varying fit function Requires software Sluggish online processing duty cycle Offline processing requires a very large data storage Offline processing requires a lot of CPU time

5. Cross-Correlation Theorem CH1 Peak = 15 CH2 Peak = 45 F [CH1*(v)CH2(v)] Peak = 30

6. Agilent Pulse Cross-Correlation Method Also, high resolution Same timing jitter as the fitting method Hitting a timing resolution limit from time base drifting Waveform splining was used to remove quantization effects for this plot 6.4 psRMS

7. Why use the Cross-Correlation Method? Universal method to find the time between the peaks of any two functions Cross-Correlation can be done with firmware => “an online solution” Currently working on a developing firmware to determine the required FPGA resources and readout speed for this method

8. Cross-Correlation with Firmware FFT, INV_FFT, FIR Filter, and Complex Multiplier are free IP cores from Xilinx Waveform DATA FIR Filter (optional) FFT Memory Stored Fourier test function Complex Multiplier INV_FFT Correlation Waveform DATA Peak Measurement Charge Measurement Time Measurement

9. Online “Spline” Artificially extend INV_FFT input array Set Re & Im part of array > Nyquist frequency to zero Possible to implement in firmware 1024 array @ 100 ps steps 8192 array @ 12.5 ps steps

10. System Block Diagram Up to 7x64 channels per cPCI card Up to 4 cPCI cards per CAMAC card MCP BLAB2 MCP MAIN cPCI CARD x7 cPCI Crate (Linux) x1 CAMAC CARD CAMAC Backplane

11. fDIRC Fiber Optic cPCI 8x 1.25Gbit Fiber Optic channels 8x 16Mbit SRAM Initiator Transfer through PCI bus Store all waveforms with a cPCI crate using Sci-Linux Linux PCI driver is currently under development

12. fDIRC Fiber Optic CAMAC 4x 1.25Gbit Fiber Optic channels USB 2.0 optional computer interface Enough IOs for all CAMAC pins

13. Action Items BLAB2 ASIC development Online cross-correlation firmware development Fiber optic firmware development Linux cPCI driver development Setup CAMAC data transfer protocol