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Radio Wave Propagation and Broadcast Regulation
Published in Skip Pizzi, Graham A. Jones, A Broadcast Engineering Tutorial for Non-Engineers, 2014
The system design for IBOC is intended to approximately replicate the primary service area of the analog channel with the digital program service, as described in Chapter 13. Although in its hybrid mode the IBOC digital signal coexists in the same channel as a station's analog transmission, the digital signals are generated as a wholly separate service—in some cases using a separate transmitter, or even separate antennas. For these reasons, propagation and reception capabilities may differ in actual practice between the two services of a given station. Moreover, it is well known that the gradual degradation of analog transmissions allows some users to tolerate listening at greater distances and lower signal strengths, accepting the increased noise and distortion that may occur. IBOC digital service may not be receivable under these conditions. It was also considered necessary for the primary digital service (“HD-1”) to degrade gracefully at the edge of the service area, so the listener would not suffer the “cliff effect.” Therefore the system was provided with the capability to blend more-or-less seamlessly from the primary digital to the analog service at the receiver, when the digital signal strength became too weak to properly receive.
IBOC Digital Radio and the State of the Digital Radio Industry
Published in David P. Maxson, The IBOC Handbook, 2007
IBOC is a form of terrestrial radio broadcasting that employs sophisticated digital radio waveforms that can deliver compact disc-like quality sound, free of interference and noise to radio listeners. The term IBOC is an acronym for In-Band On-Channel digital radio, a term that describes the use of the existing AM and FM analog broadcasting bands and channel schemes for the digital transmissions. “HD Radio” is a trade name for AM and FM IBOC digital radio systems, a trademark of iBiquity Digital Corporation, the sole proponent for a comprehensive AM/FM digital radio broadcasting (DRB) technology in the U.S.A. iBiquity licenses the mark to companies that want to use iBiquity technology and that earn, through rigorous testing, the HD Radio brand identity.
Storage and transmission of spatial sound signals
Published in Bosun Xie, Spatial Sound, 2023
In-band on-channel (IBOC) is a hybrid method of simultaneously transmitting digital radio and analog radio broadcast signals on the same frequency band (AES Staff Technical Writer, 2006b). The HD Radio is an IBOC system developed byiBiquity Digital Corporation in the USA for the frequency range of medium-wave AM broadcasting and FM broadcasting. It has been standardized by The Federal Communications Commission (FCC) as the standard of digital radio and used in the USA.
Implementation of a Regional Spectrum Sensing Based Cognitive Radio System for Digital TV White Space
Published in IETE Technical Review, 2018
Byung Moo Lee, Hyungjoon Song, Jong-Sik Lee
For the DTV band mobile WiMAX AP and MS, we used the regular WiMAX AP and MS, which are operating in the 2.3 GHz band. We used radio frequency (RF) converters and controllers to change the 2.3G Hz band to the DTV band (470∼698 MHz). Commercial WiMAX and WiFi chipsets were used for high reliability. WiMAX AP can manage frequency hopping using WiFi-based 2.4 GHz band signalling channel, and WiMAX MS has a capability of frequency hopping based on WiFi signalling from WiMAX AP.