Integrated nmr transceiver array

A method for using an integrated nuclear magnetic resonance (NMR) transceiver array, the method comprising:

• receiving a radio frequency (RF) frequency reference clock input, a RF pulse train, an enable power amplifier (PA) during transmit phase input, an enable low-noise preamplifier (LNA) during receive phase input, a select local oscillator (LO) phase input, and a receiver shut down signal input at one of the plurality of NMR transceiver circuits for use in a transmitter and a receiver of the NMR transceiver array;
• driving an off-chip coil using the transmitter with the RF pulse train;
• receiving an NMR signal using the off-chip coil at the receiver;
• processing the received NMR signal at the receiver using the enable PA during transmit phase input, the enable LNA during receive phase input, the select LO phase input, and the receiver shut down signal;
• outputting an amplified and filtered received NMR signal from the receiver.

A nuclear magnetic resonance (NMR) tool to be disposed downhole within a wellbore and integrated on a single printed circuit board, the NMR tool printed circuit board comprising:

• a complementary metal-oxide-semiconductor (CMOS) chip comprising a transceiver array of at least one of a plurality of integrated NMR transceiver circuits;
• at least one switch-based duplexer;
• at least one digitally-tunable impedance matching network;
• an analog-to-digital converter (ADC);
• a field-programmable gate array (FPGA);
• and
• a crystal oscillator,
• wherein the NMR transceiver circuit comprises:
• a transmitter that receives and outputs a radio frequency (RF) pulse train, wherein the transmitter comprises;
• a duty cycle controller for varying the output power level of the RF pulse train;
• and
• a power amplifier (PA) for driving a coil with the RF pulse train;
• and
• a receiver that receives an NMR signal and has a shut down function that allows a received receiver shut down signal to completely turn off the receiver, wherein the receiver comprises;
• a low-noise preamplifier (LNA) that differentially amplifies the received NMR signal by a first gain value;
• a variable-gain amplifier (VGA) that further amplifies the received NMR by a second gain value;
• a pair of differential mixers that are driven by local oscillator (LO) signals, receives the amplified received NMR signal from the VGA, and outputs a demodulated real in-phase (I) output and a quadrature (Q) output of the received NMR signal;
• a phase switcher that selectively flips the polarity of the positive and negative LO signals that feed each differential mixer;
• and
• a low pass filter (LPF) that receives the I output and the Q output from the pair of differential mixers, and filters then outputs the received NMR signal.