Many scientific measurements are actually a composite of two or more indirectly measured values. A distance measurement, for example, is actually a measurement of the true distance and some amount of error added together. A new method for decomposing a pair of such composite signals into their individual components in certain situations is described. The method utilizes a delay time difference between the components in each of the two composite signals to provide information necessary to reconstruct the individual components. This decomposition would allow for the possible removal of one of the components, such as in the case of unwanted noise. The method is able to distinguish between two signals with similar frequencies and amplitudes, making it a viable solution in situations where simple low- or high-pass filtering would remove needed signal information. Three successful applications of the method are described, including measurement of lateral tape motion (LTM) in a magnetic data storage tape drive and removal of additive noise from both an electrical and a mechanical system.

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Magnetic data tape is one of the most costeffective means of large scale information storage, and has the capacity to remain so in the future. Many challenges must be met in order to improve the storage density of magnetic tape systems and keep up with customer demands. One of these challenges is to minimize the relative motion between the read/write elements in the tape drive and the data tracks on the tape, also known as lateral tape motion (LTM). Modern closed-loop servo-based track following techniques are able to compensate for a large portion of the LTM events experienced, but care must still be taken in design of both the tape drive and tape media in order to minimize the negative effects of LTM. This paper details a study in which a new delay-integration method is applied to LTM measurement. The advantages and disadvantages of the method are discussed, and a comparison is made with previous LTM measurement methods. The delay-integration method is then applied to measure the change in LTM amplitude along an unsupported region of tape for several different tape samples. As many tape systems place the read/write head in the center of an unguided region, information about the behavior of tape in this situation could be used to minimize LTM, allowing for smaller data tracks and increased storage density.