The shape of a resulting pulse (coherent interference superimposed to Gaussian pulse) along the linear optical fiber is determined by using attained analytical expressions. These analytical expressions enable the investigation of the influence of arbitrary dispersion order on pulse propagation. Individual and joint influence of second- and third-order dispersion on the transmission quality is examined in this paper. Pulse shape, eye diagram and bit error rate (BER) are used to represent in the best manner the above-mentioned influences. (C) 2008 Elsevier GmbH. All rights reserved.