Abstract: Proposed is a method of multichannel GSR detection for improving measurement accuracy and noise/artifact rejection in measurement of the galvanic skin response on the skin of an individual. The method comprises multichannel GSR signal detection with at least two electrode pairs that are attached to a body of an individual in contact with the skin in different locations, wherein the GSR signals are measured and recorded while the level of excitation of the nervous system of the individual varies. The method is based on the fact that only events that show high temporal correlation in two or more signal registration channels are considered to be physiological GSR reactions. Time-domain correlation allows not only improved detection of high-amplitude events but also improved sensitivity to smaller events that were ignored in standard bipolar GSR recording.

Abstract: A spectrum analyzer with a compensation circuitry for prevention of measurement accuracy deterioration due to local oscillators phase noise.

Abstract: A read amplifier system for connection through interconnects to a magnetoresistive (MR) head includes two input transistors, two bias transistors connected to the two input transistors by common source connections, a bias voltage control circuit connected to base terminals of the two bias transistors, a common mode voltage control circuit connected between first and base terminals of the input transistors to provide feedback from the first terminals to the base terminals, and a compensating circuit connected between the outputs of the amplifier system and the base terminals of the input transistors for providing a feedback from the outputs to the base terminals. The two base terminals of the input transistors are respectively connected to the interconnects of the MR head. The bias voltage control circuit applies a bias voltage to base terminals of the two bias transistors, and through the common sources to the base terminals of the input transistors, and thereby across the MR head.

Abstract: A spectrum analyzer with a compensation circuitry for prevention of measurement accuracy deterioration due to local oscillators phase noise.

Abstract: An apparatus for substantially eliminating a switching voltage transient in a magnetic recording system so as to minimize a write-to-read recovery time includes a first bias enable switch, a bias current source responsive to the first bias enable switch, an MR sensor for receiving a bias current from the current source, and a read amplifier being capacitively coupled to the MR sensor. The bias current flowing through the MR sensor produces the switching voltage transient due to the RC time constant presented by the input of the read amplifier. The apparatus includes a first compensating circuit for generating a compensating voltage transient having a polarity substantially equal and opposite to the switching transient. The first compensating circuit is electrically coupled to the MR sensor, and a superposition of the switching voltage transient and the compensating voltage transient is substantially zero.