×

Direct digital synthesizer, direct digital synthesizer for transmission and detection, and MRI apparatus

  • US 7,818,359 B2
  • Filed: 09/18/2006
  • Issued: 10/19/2010
  • Est. Priority Date: 09/22/2005
  • Status: Active Grant
First Claim
Patent Images

1. A direct digital synthesizer for transmission and detection, comprising:

  • a transmitting phase accumulator for outputting phase data (P1) with a clock frequency f1;

    a transmitting waveform LUT for outputting transmitting signal amplitude data (T) in accordance with said phase data (P1);

    a curtailing device for outputting phase data (P2) with a clock frequency f2 (<

    f1) by implementing curtailing process to said phase data (P1) and also outputting additional data (A) for compensating for phase information disappeared with said curtailing process;

    wherein said additional data (A) is assigned the binary value indicating which phase region said phase data (P2) belongs according to ‘

    00’

    =0°

    to 360°

    , ‘

    01’

    =360°

    to 720°

    , ‘

    10’

    =−

    360°

    to −

    720°

    , and ‘

    11’

    =−

    360°

    to 0° and

    said additional data (A) is assigned according to 360°

    times an integer where ‘

    00’

    is integer 0, ‘

    01’

    is integer 2, ‘

    10’

    is integer −

    2, and ‘

    11’

    is integer −

    1;

    an interpolating device for outputting phase data (P3) with a clock frequency f3 (>

    f2) by implementing interpolating process in accordance with said phase data (P2) and said additional data (A) outputted from said curtailing device;

    and a detecting waveform LUT for outputting detecting signal amplitude data (S) in accordance with said phase data (P3) outputted from said interpolating device.

View all claims
  • 2 Assignments
Timeline View
Assignment View
    ×
    ×