Evolution of digital radio testing in Brazil

Introduction

Brazilian radio broadcasters have always expressed interest in ensuring that digitalization is implemented on the same frequency as is used for analog broadcasting, so that digital sound broadcasting transmission can be introduced gradually and economically.  To that end, they have indicated their preference for digital sound broadcasting systems that take account of hybrid or simulcast transmission, in which analog and digital signals may be combined on the same frequency used by the transmitter.

To that end, two digital sound broadcasting systems approved by the International Telecommunication Union (ITU) may be compatible with the interest of Brazilian broadcasters:

a)   In-Band On-Channel (IBOC) system, of the United States, developed by iBiquity Digital Corporation, approved in Recommendation ITU-R BS 1514-1, “System for digital sound broadcasting in the broadcasting band below 30 MHz,” for the medium wave band, and in Recommendation ITU-R BS. 1114-5, “System for terrestrial digital sound broadcasting to vehicular, portable and fixed receivers in the 30-3000 MHz frequency range,” for the FM band.

b)  Digital Radio Mondiale (DRM) system, developed by the European consortium of the same name, approved in the same Recommendation ITU-R BS. 1514-1, for medium, tropical, and short wave bands.

Test authorizations

Anatel has granted test authorizations in accordance with the interest expressed by transmitters in conducting tests.  There is no Anatel restriction on the system it is requested to test.  The objective of tests is to evaluate the following:

a)          System performance, taking account of the following requirements:

•     Audio quality

•     Coverage area

•     Robustness as regards noise, interference, and multiple routes

b)          Compatibility of the digital signal with existing analog signals (apart from short wave):

•     Impact of digital signal on reception of simultaneously transmitted analog signal

•     Impact of digital signal on reception of analog signals on the same and adjacent channels

•     Compatibility of coverage area

National Telecommunications Agency
ANATEL-Brasil