1. TMBF Features
Guenther Rehm

2. Outline Bunch counter Bunch Min/Max on ADC/DAC
Per bunch function (FB/Ex/FB+EX/Off) and gain (-1..1)
Bunch select for observation
Excitation with swept sine wave
I/Q demodulator with integration over programmable number of bunches
03/04/2008
TMBF Features

3. Bunch Counter FPGA clock is ¼ of RF clock
Internal bunch counter advances every 4 bunches, but also knows which of the four processing chains is going to the output.
Can be re-synchronised with an external trigger (to within 4 bunches)
Counter is used by all other functions to reference bunch
03/04/2008
TMBF Features

4. Development path Step FPGA design Control System User Interface 1
System Generator (from ESRF)
EPICS
(Register Interface)
Matlab
(From ESRF) 2
System Verilog (same registers)
Matlab (ESRF+additions) 3
System Verilog (interface changes)
(sensible channels)
EDM screens
03/04/2008
TMBF Features

5. Spectral Domain Record up to 32000 turns and FFT
Remove revolution frequency harmonics
230mA
170mA
125mA
03/04/2008
TMBF Features

6. Time Domain Compared to Fill Pattern from Photon Counting
03/04/2008
TMBF Features

7. Per Bunch Min/Max for ADC/DAC
03/04/2008
TMBF Features

8. Per Bunch function: Example damp all bunches, excite one, knock out
03/04/2008
TMBF Features

9. Grow/Damp Measurement
Excite mode for a brief period
switch off excitation, close loop
record mode amplitude, fit decay
repeat for different modes
vary gain
03/04/2008
TMBF Features

10. Damping time per mode
03/04/2008
TMBF Features

11. Sine Wave excitation and detection
Programmable sweep from 0 to 250MHz
NCO produces cos/sin, cos goes to excitation
Input is mixed with cos and sin, producing I/Q
I/Q is integrated for programmable number of bunches
Waveform with one point per frequency in the sweep is produced
Can work on either all or one bunches
Finer frequency resolution than FFT
Sensitivity can be achieved either through strength of excitation or duration of integration
Can operate invisibly to user beam
03/04/2008
TMBF Features

12. Tune measurement of individual bunches
03/04/2008
TMBF Features

13. Example: Tune Tracking
03/04/2008
TMBF Features