FINE RESOLUTION PHASE-SHIFTER FOR TPPI IMPLEMENTATION

点击翻译按钮获取中文摘要

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Implementation of multi-quantum coherence (MQC) requires time delays and phase advances in small steps. Whereas we can produce very accurate timing using specialized ECL modules, accurate phase incrementing is a formidable task. To address this issue we procured a 6-20 GHz 12-bit phase shifter which we will use in our initial MQC work that relies on uniform spectrum excitation. A hardware control will be based on USB interfaced FPGA modules, which we already have. Phase cycle tables and look-up tables will be downloaded via USB and the unit will be controlled in real time using pulse sequence and phase advance/reset signal lines from the system DSP real-time controller. This will enable us to implement Time-Proportional Phase Incrementation (TPPI) for the MQC work.