Comments on "Minimum variance beamforming with phase-independent derivative constraints" [with reply]

The commenter points out that the idea of controlling only the magnitude response of a beam to achieve a flat main beam response, as discussed in the above-titled paper by C.-Y. Tseng (ibid., vol.40, no.3, p.285-94, Mar. 1992), is not new and was discussed by M.H. Er (1988). The author apologizes for the oversight and points out that the paper also covers issues that were not addressed by Er.<
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