Results of the ISDB-T system tests, as part of digital TV study carried out in Brazil

Since the year 2000, Mackenzie Presbyterian University has been carrying out lab and field tests to evaluate the performance of current DTV systems, with the aim of providing backing for the Brazilian Government´s decision on the standard to be adopted. This paper presents the results of tests using the Japanese DTV system ISDB-T. Initially, the tests were done using a first generation prototype of the ISDB-T DTV set-top box. When DTV transmissions began in Japan in November 2003, the Brazilian tests were repeated using several new commercial set-top boxes. The main tests accomplished in 2000 were: measurement of the C/N ratio, behavior of the signal with multipath, Doppler effect and immunity to impulse noise. In 2003/2004, these tests were repeated using new receivers to analyze the evolution of the system. Furthermore, two new tests were introduced: resilience to phase noise and simultaneous transmission of two types of modulation in the same TV channel, in order to evaluate the band segmentation. Also, a one-segment DTV receiver (1STV) in a portable handset was tested in the laboratory.