Optimized channel controller for NMR apparatus

• US 7,102,349 B2
• Filed: 03/08/2006
• Issued: 09/05/2006
• Est. Priority Date: 04/08/2004
• Status: Expired due to Fees

• Current Assignee: Agilent Technologies, Inc.
• Original Assignee: Varian Incorporated (Agilent Technologies, Inc.)
• Inventors: Hornung, Phillip A.
• Primary Examiner(s): Arana, Louis M.
• Application Number:
  US11/370,647
• Publication Number:
  US 20060170422A1
• Time in Patent Office: 181 Days
• Field of Search: 324/312, 324/300, 324/322, 324/318
• US Class Current: 324/312
• CPC Class Codes: G01R 33/3607 RF waveform generators, e.g. frequency generators, amplitude-, frequency- or phase modulators or shifters, pulse programmers, digital to analog converters for the RF signal, means for filtering or attenuating of the RF signal
• CPC Class Codes: G01R 33/54 Signal processing systems, e.g. using pulse sequences ; Generation or control of pulse sequences; Operator console
• CPC Class Codes: G01R 33/543 Control of the operation of the MR system, e.g. setting of acquisition parameters prior to or during MR data acquisition, dynamic shimming, use of one or more scout images for scan plane prescription G01R33/546 takes precedence

Abstract

A controller for apparatus assuming a sequence of precisely synchronized states in accordance with a lengthy event stream is realized in an architecture comprising a register layer comprising a plurality of latched registers for receiving event descriptors and parameters from a bus and a computational/logical layer for operations on/among certain of said parameters for presentation to external operational devices. An RF controller controlling frequency, pulse width, amplitude with precise timing for magnetic resonance applications is one example and a magnetic gradient controller controlling vector magnitude and orientation is another.

Claims

1. An NMR apparatus for study of the content of a sample volume, comprising:

a polarizing magnet for establishing a preferred direction for nuclear spins,

a source of RF energy controllable for selected phase, amplitude and frequency,

an RF controller comprising a clock device for synchronous operation, comprising a processor device for

initializing RF operational parameters for defining each said state to default values thereof,

prescribing a progression of states at subsequent adjacent discrete times, comprising

assigning a duration to each state,

characterizing each state by the changes in value from the preceding state of one or more said parameters,

transferring only said changed values of said RF parameters to a corresponding plurality of latched data registers, said latched registers corresponding to operand parameters, and also transferring content of said latched registers to a respective computational cell and computing the resultant of said operand parameters and retaining same in a latched resultant register,

communicating the parameters retained from each said latched register and each said resultant register and corresponding duration to an asynchronous-to-synchronous buffer,

presenting said parameters and resultants to an output in synchronous relation to said clocking device, and

maintaining said output for said corresponding duration, and

causing said output to operate said source of RF energy in accord with said output.

2. The NMR apparatus of claim 1, wherein said computational cell modifies said RF phase by an addition operation and both communicates the result of said addition back to said latched register and to said computational cell.

3. The NMR apparatus of claim 1, further comprising

magnetic gradient apparatus for imposing a magnetic gradient vector field on said sample volume, and

a magnetic vector controller comprising another processor in synchronous relation with said clock for controlling said magnetic vector apparatus to establish the orientation and magnitude of said magnetic gradient vector and maintain the persistence of said vector for a selected gradient vector duration.

4. An NMR apparatus for study of the content of a sample volume, comprising:

a polarizing magnet for establishing a preferred direction for nuclear spins,

a source of RF energy controllable for selected phase, amplitude and frequency,

magnetic gradient apparatus for imposing a magnetic gradient vector field on said sample volume, and

a magnetic vector controller comprising a clock device for synchronous operation and a processor in synchronous relation with said clock to establish a sequence of discrete states comprising the orientation and magnitude of said magnetic gradient vector and to maintain the persistence of said vector for a selected gradient vector duration, said controller comprising;

(a) a plurality of latched registers for receiving and retaining corresponding datums from an input bus and wherein at least one said latched register comprises an argument portion of said datum, an increment portion of said datum and an adder for modifying said argument through addition of said increment portion and communication of the result thereof both to a corresponding mathematical register and to replace the value held in said argument portion of said at least one latched register,

(b) at least one latched mathematical register array for receiving and retaining corresponding datums from said corresponding latched register, said latched mathematical register array comprising a computational module for combining said datums in accord with a mathematical rule to yield a computed result datum, and the corresponding latched mathematical register adapted to retain said computed result datum, and

(c) a plurality of FIFO portions, each portion in correspondence with one said latched register and latched mathematical register, each said latched register and latched mathematical register in corresponding relationship with one said FIFO portion, whereby a FIFO assembly comprising said FIFO portions contains a sequence of said states.

5. The NMR apparatus of claim 4, wherein said computational cell modifies said magnetic vector gradient by an addition operation and both communicates the result of said addition back to said latched register and to said computational cell.

6. The NMR apparatus of claim 4, further comprising RF controller apparatus comprising an RF output register and a clock device for synchronous operation with said magnetic vector controller, said RF controller comprising a processor for presenting a sequence of RF states of prescribed discrete persistence to said RF output register.