AP7 – 99 – The TVG method closely approximates the convolution of the distribution of the horizon gain of the earth station antenna and the propagation mode (1) path loss. This method may produce slightly smaller distances than those obtained by an ideal convolution. An ideal convolution cannot be implemented due to the limitations of the current model for propagation mode (1). The propagation mode (1) required distance, at the azimuth under consideration, is taken as the largest distance developed from a set of calculations, each of which is based on equation (4) of the main body of this Appendix. For convenience, in these calculations, this equation may be rewritten for the n-th calculation in the following form: Lb(pν)Ge(pn)Pt Gx Pr(p) dB (123) with the constraint: %50 for 2 100 /for 2 p p p p p p p n n n ν where: Pt, Pr(p): as defined in equations in § 1.3 of the main body of this Appendix where p is the percentage of time associated with permissible interference power Pr(p) Gx: maximum antenna gain assumed for the terrestrial station (dBi). Tables 7 and 8 give values for Gx for the various frequency bands Ge(pn): the horizon gain of the coordinating earth station antenna (dBi) that is exceeded for pn%of the time on the azimuth under consideration Lb(pv): the propagation mode (1) minimum required loss (dB) for pv% of the time; this loss must be exceeded by the propagation mode (1) predicted path loss for all but pv% of the time.The values of the percentages of time, pn, to be used in equation (123) are determined in the context of the cumulative distribution of the horizon antenna gain. This distribution needs to be developed for a predetermined set of values of horizon antenna gain spanning the range from the minimum to the maximum values for the azimuth under consideration. The notation Ge(pn) denotes the value of horizon antenna gain for which the complement of the cumulative distribution of the horizon antenna gain has the value corresponding to the percentage of time pn. The pn value is the percentage of time that the horizon antenna gain exceeds the n-th horizon antenna gain value. The procedure in § 4.1 may be used to develop this distribution. For each value of pn, the value of horizon antenna gain for this time percentage, Ge(pn), is used in equation (123) to determine a propagation mode (1) minimum required loss. The propagation mode (1) predicted path loss is to exceed this propagation mode (1) required loss for no more than pv% of the time, as specified by the constraint associated with equation (123). A series of propagation mode (1) distances are then determined using the procedures described in § 4 of the main body of this Appendix.