The paper presents a new approach for intellectual property protection of audio products when they are distributed via computer networks or radio broadcasting. The presented approach is based on a method for digital watermarking, performed in the spectrum domain, using a Complex Hadamard Transform (CHT) with a specific matrix, in which only 1⁄4 of the elements are complex numbers. In correspond...

Because of its unique digital transmission, HD Radio® requires new methods and standards to measure and predict signal coverage, relative to analog FM. Because analog FM reception quality is known to decline gradually with degraded RF signal quality, analog FM service may be quantified in simple terms of signal strength. With digital audio broadcasting, reception quality remains ‘perfect’ until...

In recent years, the wireless industry has shown great interest in OFDM systems. Indeed, such systems have been adopted in a variety of wireless applications such as digital audio broadcasting (DAB) and digital video broadcasting (DVB). Moreover, OFDM has also been proposed for indoor wireless networks and fixed wireless broadband access [1,2]. This growing interest was due to the realisation t...

In this paper, transmission rate enhancement schemes for DRM (Digital Radio Mondiale), which is a worldwide standard for digital AM and FM broadcasting in the AM and FM bands below 170 MHz, are presented and compared. The data rate of the legacy DRM system is supported up-to 186kbps with 16QAM and MLC (Multi-level Coding) at 100 kHz bandwidth. However, this rate is not sufficient to achieve new...