Research on Evaluation Model of Digital-analog Interference for IBOC

HD Radio standard can realize the smooth transition from analog to digital using "in-band on-channel (IBOC)" technology, which is the most advantageous choice for analog broadcasting digitized. In HID Radio Hybrid and Extended waveform type, the digital signal employs the same carrier with the analog signal, and is transmitted on both sides of the analog FM signal. Since the digital carrier adjacent analog signal, the core to implement IBOC is the interference problem of digital signal to analog signal at the beginning of broadcasting digitized. For the interference evaluation model, this paper apply noise masking ratio (NMR) and objective evaluation level (ODG) as a combined evaluation factor for digital-analog interference in IBOC broadcasting. This interference evaluation method which utilizes the comprehensive advantages of NMR and ODG, with more scientific than the SNR measurements, can be widely used as an evaluation index for audio interference.