 as the DLL), allows a proper characteri- zation of the cycle-slipping phenomenon of the former and the loss-of-lock phenomenon of the latter. The "periodic extension solution" [16] that has traditionally been applied in such situations is shown to be identical to the "renewal process solution" only for a first-order loop. Most significantly, the "intrinsic" or "self" noise of the DLL, which is always (even in the absence of the additive Gaussian noise) present in the loop, and which depends on the loop tracking error, is accounted for in the renewal process approach. In many applications, this intrinsic noise is dominant and cannot be neglected. We hasten to add that Meyr's work was originally motivated by the necessity of performing precise velocity and distance measurements for modern mass transportation systems [28], [29] and as such his discussions are primarily concerned with the coherent DLL as originally discussed in Pseudonoise Code Tracking in Direct-Sequence Receivers [1]. More recently, this work was extended to the non-coherent DLL by Polydoros [30]. 2.11 REFERENCES [1] J. J. Spilker, Jr., "Delay-lock tracking of binary signals," IEEE Trans. Space Electr. and Telem., vol. SET-9, No. 1, pp. 1-8, march 1963. [2] J.J. Spilker, Jr., and D. T. Magill, "The delay-lock discriminator-ar optimum tracking device," Proc. IRE, vol. 49, No. 9, pp. 1403-1416, September 1961. [3] W.J. Gill, "A comparison of binary delay-lock loop implementations," IEEE Trans. Aerosp. and Electr. Syst., vol. AES-2, pp. 415-424, July 1966. [4] P.T. Nielsen, "On the acquisition behavior of binary delay-lock loops," IIEEE Trans. Aerosp. and Electr. Syst., vol. AES-11, pp. 415-418, May 1975. [5] M.K. Simon, "Noncoherent pseudonoise code tracking performance of spread spectrum receivers," IEEE Trans. Commun., COM-25, No. 3, pp. 327-345, March 1977. [6] H. P. Hartmann, "Analysis of a dithering loop for PN code tracking," IEEE Trans. Aerosp. and Electr. Syst., vol. AES-10, No. 11, pp. 2-9, January 1974. [7] T. C. Huang and J.K. Holmes, "Pe