| Due to inadequate spectrum resources and increasing demands for high quality multimedia services, traditional analog broadcasting is being migrated into digital radio around the world. This dissertation focuses on the development of several innovative broadcasting technologies and the design of so-called Broadband Digital Radio (BDR) system, which is suitable for digital audio and data broadcasting in FM and AM channels. The new broadcasting system synergistically integrates frequency hopping, LDPC coding, hierarchical modulation and band aggregation techniques to increase the data rate, improve spectrum efficiency, and at the same time, provide the spectrum flexibility necessary in high quality audio and multimedia services.;One of the key features in the BDR is the powerful hierarchical modulation scheme that offers significant performance enhancement over existing schemes (e.g., DVB-T). In this dissertation, we present a novel decoding algorithm for the hierarchical modulation. Unlike the traditional hierarchical demodulation approaches which suffer from serious inter-layer interference (ILI), the proposed method exploits the structure information of the secondary layer to mitigate the ILI impairment, thereby offers significant gains in reception performance.;For the digital network, frequency planning is needed as in other digital broadcasting signals. Most importantly, the single frequency network (SFN) architecture will be used in the BDR deployment. The hierarchical modulation technique is also adopted in the SFN to provide both global and local information. Accordingly we develop a low-complexity successive interference cancellation (SIC) algorithm to ILI and inter-cell interference (ICI) in the HM based SFN. The performance evaluation and decoding complexity comparisons indicate that the proposed structured SIC approach offers a good performance-complexity trade-off, especially for the HM-based SFN scenarios.;Finally, a BDR prototype has been developed on a personal computer (PC) based software defined radio (SDR) platform. Numerical results and initial laboratory tests demonstrate significant performance advantages of the new design over existing systems such as the Digital Radio. |
