This article describes experimental propagation\nmeasurements of DTV signals in the urban region of Curitiba. A\ndigital TV analyzer manufactured by Rohde & Schwarz, model\nETL was used [1], which is able to differentiate open TV channel\nsignals received via different paths. At each measuring location,\nthe geographical coordinates, the relative intensity, the relative\ndelay of each of the ten most intense echoes received, the\nrecording time, and the channel power were recorded. A vertical\nmonopole antenna tuned to the channel frequency and mounted\ntwo meters above ground level on the top of a special purpose\nvehicle was used as the receiving antenna. Signal frequency\nspectrum and the subjective quality of the received signal were\nsimultaneously observed. Both the path loss and the echo pattern\nwere measured. 1580 samples were recorded, taken\napproximately five meters apart in various regions of the city and\nwere compared with current propagation models. The power and\ndelay of every multipath version was checked to evaluate the\nefficiency of the guard interval. The effects of distance and\nelevation of the reception site were investigated, as well as the\npresence of channel-modifying obstacles. Analysis of the results\nincluded the comparison of received power measurements with\nthe Okumura-Hata model calculations. The multipath delay data\nwas analyzed as per recommendation ITU-R P.1407 [2].\nPreliminary results show the robustness of the ISDB-TB system\nagainst UHF propagation in Curitiba. Some aspects of the\nmeasurements elicit further investigations that can be carried out\nwith the same resources.
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