Patent
Radio frequency receiver for a NMR instrument
TLDR
In this paper, a receiver processes an NMR signal to produce a baseband image information signal from which two quadrature component signals are derived, and the resultant signal is filtered to remove extraneous signals outside the image information band.Abstract:
A receiver processes an NMR signal to produce a baseband image information signal from which two quadrature component signals are derived. An intermediate frequency section mixes the received NMR signal with two reference signals to shift the image information into a frequency band having a bandwidth BW and centered at a frequency that is 1.5 times the bandwidth BW. The resultant signal is filtered to remove extraneous signals outside the image information band. An analog to digital converter samples the filtered signal at a rate that is twice the bandwidth BW and digitizes the samples into a digital signal. A quadrature detector derives I and Q output signals from the digital signal by alternately selecting digital samples and negating every other sample selected for each of the I and Q output signals. The quadature detector also digitally filters the I and Q signals which are then used to construct an NMR image.read more
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Patent
Wireless local area network (WLAN) technology and applications including techniques of universal frequency translation
David F. Sorrells,Michael J. Bultman,Robert W. Cook,Richard C. Looke,Charley D. Moses,Gregory S. Rawlins,Michael W. Rawlins +6 more
TL;DR: Frequency translation and applications of same are described in this paper, including wireless local area network (WLAN) applications such as IEEE Standard 802.11 WLANs, such as, but are not limited to, frequency down-conversion, frequency up-concversion, enhanced signal reception, unified downconversion and filtering, and combinations of same.
Patent
Method and system for down-converting an electromagnetic signal
David F. Sorrells,Michael J. Bultman,Robert W. Cook,Richard C. Looke,Charley D. Moses,Gregory S. Rawlins,Michael W. Rawlins +6 more
TL;DR: In this paper, the authors proposed a method for down converting a modulated carrier signal to a demodulated baseband signal, which requires that at least some of the energy stored in the first storage device is discharged when the first switch is off.
Patent
Simplified high frequency tuner and tuning method
TL;DR: In this article, a signal of interest having a predetermined maximum bandwidth is mixed with a local oscillator signal, which has a frequency that is an integer multiple of the channel spacing.
Patent
System and method for enabling a software developer to introduce informational attributes for selective inclusion within image headers for medical imaging apparatus applications
Qiang Ma,Robert Haworth +1 more
TL;DR: In this paper, a system and method for enabling a developer to introduce informational attributes suitable for selective inclusion within image headers is described, along with an interactive computer for generating software files of image header definitions from the table of defined informational attributes.
Patent
Method and system for down-converting and up-converting an electromagnetic signal, and transforms for same
David F. Sorrells,Michael J. Bultman,Robert W. Cook,Richard C. Looke,Charley D. Moses,Gregory S. Rawlins,Michael W. Rawlins +6 more
TL;DR: In this paper, the authors described a system for down-converting and up-concussing an EM signal by recursively operating on approximate half cycles (½, 1½, 2½, etc.) of the carrier signal.
References
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Patent
Magnet shimming using information derived from chemical shift imaging
Gary H. Glover,Grant T. Gullberg +1 more
TL;DR: In this article, a method for shimming a magnet in a nuclear magnetic resonance (NMR) system employs measurements of the magnetic field obtained from chemical shift imaging (CSI) of a homogeneous phantom.
Patent
Method and apparatus for feedback control loop bandwidth and phase margin regulation
TL;DR: In this paper, the authors propose a method and apparatus for providing selfadaptive feedback control loop bandwidth and phase margin regulation automatically, to rapidly and predictably closely compensate for externally-caused bandwidth and margin changes, such as caused by changing load inertia presented to an actuator.
Journal ArticleDOI
Microcomputer based phase sensitive detector
TL;DR: A fully digital phase sensitive detector which utilises a microprocessor card and has been used for the detection of the signal in a wide line NMR spectrometer substantially confirming the theoretical results.