chronism). Performance comparisons are made in terms of output SNR between the optimal structures and the classical wideband radiometer. Also considered in [10] are the effects on the maximum-likelihood struc- tures produced by (1) assuming that the signal of interest is formed by pass- ing the "ideal" digitally modulated signal through a band-pass filter that may severely distort the waveform and (2) assuming the presence of correlation among the symbols in the transmitted sequence. The practical significance of the assumptions in (1) and (2) are that filtering is often intentionally per- formed on spread-spectrum type signals to make them appear more "noise- like," whereas sequences of correlated symbols naturally come about when modulations such as minimum-shift-keying (MSK) are employed to produce desirable spectral shaping. While all of the structures that are developed in [10] assume a uniform a priori probability distribution on the input symbols, a simple modifica- tion, e.g., a non-linear weighting of each of the terms contributing to the sum in (1.79), can be performed to make the results applicable to other distributions. In [11], Krasner continues his work in [10] by developing maximum-like- lihood estimators of carrier phase and symbol epoch for quadriphase mod- ulated signals, again under the assumption that the symbol sequence is unknown and that the presence of data information on these symbols is of no interest to the receiver. As in [10], the case of interest is low-symbol SNR and the resulting maximum-likelihood structures that are derived are fur- ther simplified to correspond to this case. The effects of filtering and corre- lated symbols are also considered. Finally, we wish to point out the existence of an excellent tutorial style arti- cle by Glenn [12] (also presented at MILCOM'82 but not included in the proceedings), which identifies the key system parameters and their interre- lation in determining the LPI performance of airborne command post/satel- lite links operating at super high fr