IBOC Technology

The IBOC signals are still in the same frequencies used by AM, FM, and HD Radio stations today. They operate on different channels than analog transmissions, but if the receiver doesn’t have the ability to read digital signals yet, we will still be able to tune in on old frequency. All we need is a new receiver or car stereo with an antenna input jack or other mobile device or laptop computer with a headphone jack. As we mentioned before, the only difference between digital radio and analog is IBOC transmission encoding.

IBOC Technology: What Is It?

In the near future, traditional subscription radio services will be replaced by a system known as IBOC Technology. This word refers to a 10-10 form of digital broadcasting where the mobile device is used to generate a local station. The IBOC signal is then picked up and transmitted by traditional terrestrial stations, cordless receivers, and wireless devices such as tablets and laptops. IBOC technology can also be delivered on over-the-air channels similar to the old analog broadcasts of today’s radio stations. But IBOC transmissions and analog signals will be in competition. When will this happen? That depends on the FCC’s ability to regulate the airwaves.

IBOC technology is expected to replace traditional radio broadcasting because it can deliver digital audio channels at a fraction of the cost while providing many of the same features. The principal advantage that IBOC technology provides over traditional radio broadcasting is that it enables listeners to listen to multiple stations through their portable digital devices in real-time.
IBOC technology is the result of the collaboration of two major industry players. The first is the public broadcasting industry, which has successfully launched its own digital services, and the second is an electronics manufacturer, which has been working to develop a handset that can support digital broadcasts.

IBOC technology was developed by broadcasters and electronics manufacturers to replace traditional radio broadcasts. Traditional radio channels are broadcast on a fixed frequency indicated either by -F or -FM in the station’s call letters. This means that both non-digital radio receivers and mobile devices can work with these frequencies. This is because non-digital radios and mobile devices are capable of tuning only to the frequencies indicated by the -F or -FM call letters.
IBOC technology, in contrast, uses a broader range of frequencies that can only be detected by IBOC digital receivers. This means that traditional radios will not be able to detect radio signals carried by IBOC technology in real time because they cannot respond to digital transmissions.

IBOC technology is a form of digital broadcasting that enables some FM stations to operate at lower frequencies while increasing the number of stations that can be transmitted at one time on the same frequency. This can deliver more programming with higher-quality sound while reducing interference and eliminating static within broadcast areas.

The architecture of IBOC:

The RF frequencies used by digital radio are the same as those used by FM, AM, and HD Radio stations, so digital radio is compatible with existing radios and sets. The IBOC signal is a digital transmission, sent in the Digital Audio Broadcasting (DAB) format. Think of it as if radio stations were broadcasting in MP3 format, but instead of stereo audio being sent over two channels, it’s all on one channel. In other words: We can still tune in on our favorite old frequency.

To decode the IBOC transmission into regular analog audio that our car will recognize, all receiver needs to have enough memory to record and store information about each symbol. This is why digital radios, car stereos, and portable digital devices are all being released later.

The IBOC format uses one frequency for each station, which can be shared by multiple frequencies in the same area. This means that all stations within a city share the same bandwidth, and therefore it is possible for listeners to listen to every station on their “local” channels. The two or three stations with the strongest signals will be heard clearly, and in most cases, headphones are not necessary. That’s because there is a sufficient amount of information in each transmission to allow an analog-quality stereo mix to be created in a home receiver.

IBOC Implementation Techniques:

The IBOC technology uses the newest developments in digital signal processing and has made it possible to create a hybrid analog/digital radio system where both types of signals (analog and digital) coexist in the same radio frequency band.

There are three main components to the IBOC system:

• The first is a type of advanced quadrature amplitude modulation or QAM. This is used for encoding the digital signal on traditional AM and FM analog channels. 
• The second component is time domain multiplexing for producing a stereo signal from music CDs encoded into DAB format. 
• The third component is a digital type of stereo FM broadcasting.

A digital audio bit stream is created and recorded on a CD, then read into the digital encoding section of the digital stereo multiplexer. The bit stream is divided into eight digital data streams with as many as 96 kbit/s. The 96 kbit digital data streams are converted to four 56 kbit data streams using advanced compression technology developed specifically for this application. These 56-kbit-per-second streams are modulated onto subcarriers spaced 12 kHz apart.

IBOC modes of operation:

There are three modes of operation: 

• Single-channel mode
• Multi-channel mode
• Analog/digital simulcast mode. 

The single-channel and multi-channel modes are for AM and FM stations, respectively, while the simulcast mode is used by AM stations that wish to broadcast a digital signal on the same channel.

The same digital stereo multiplexer or DSX encoder is used for all IBOC stations but with different configurations as described below. Because the DSX encoder is a standard piece of equipment, its purchase costs are low. This is an important consideration since it adds digital processing to an older FM transmitter system. Digital processing can quickly drain the power supply of a transmitter rendering it inoperable.

DAB and its Benefits:

Several countries have adopted the DAB standard, including Norway, Sweden, and Denmark. The DAB system provides many benefits in addition to improved sound quality:

• IBOC Benefits: There are many benefits of IBOC that may not be provided by a digital satellite radio or other digital broadcast methods available today:
• IBOC Disadvantages: 
  • Like any new technology, IBOC has its trade-offs. Most of these can be overcome with careful planning for each individual station.