Abstract
An analysis of the response of a towed array to the modal field in isovelocity shallow water is presented. In general, the response consists of a coherent sum over all the modes. However, when the source is endfire‐on to the array, or in that vicinity, the towing motion introduces a certain amount of range averaging into the response to the farfield radiation. A criterion is given, in terms of the interference length between the two lowest order modes in the field, for the degree of range averaging required to reduce the output of the array to an incoherent sum over the modes. This sum is associated with a set of virtual sources distributed in azimuth, each of which is associated with a particular normal mode. This means that some signal energy is rejected by the array, which results in a reduction in the signal gain. At the same time beam broadening, or in extreme cases beam splitting, arising from the angular spread of the virtual sources, occurs and this may give rise to a significant bearing error.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
