Monday 24 June 2019

Software-Defined Radio with Android Smartphones


Software-defined radio (SDR) is one of the most important wireless communication technologies. It is a unique type of radio system that can tune to any frequency band. The SDR platform is generic, that is, one platform supports various signals of different frequencies.

Earlier, SDR hardware was designed only to support high-end computer systems and desktop computers. However, with recent advancements in smartphone technology and availability of affordable smartphones, developers have started working on SDR support for mobile phones.

RTL-SDR dongles can easily perform the function of an SDR receiver using an Android smartphone with on-the-go (OTG) support. Fig. 1 shows an RTL-SDR dongle connected to an Android smartphone.

RTL-SDR dongles provide the functionality to receive a signal in the 25MHz-1.75GHz frequency range. The system/radio receiver designed using an RTL-SDR dongle can also be used to study digital communications by electronics and communications engineering students.

An RTL-SDR dongle is mainly a DVB-T/DVB-T2 signal receiver dongle to view terrestrial TV channels. But developers realised that the RTL2832U chip present in these dongles can also be used as SDR hardware. The dongle is set in test mode and acts as an SDR receiver. DVB-T and DVB-T2 dongles are shown in Fig. 2.
The antenna provided with the dongle (see Fig. 3) is suitable for signal reception. It comes with a magnetic base, so it can be mounted on a metallic surface.
You can use any of the two USB dongles (shown in Fig. 2) for SDR applications. The setup for an Android smartphone based SDR system with only signal reception capability is explained in the following sections.

The SDR system and Android smartphone can be used to perform the following functions:

1. The SDR dongle can make Android tablet/phone compatible for FM signal reception and listening to FM broadcasts, which is helpful for devices without FM option.

2. The SDR implemented using Android smartphone and RTL-SDR can receive FM broadcast channels.

3. The amplitude modulation (AM) signal can be demodulated using the setup between the supported frequency ranges.

4. The SDR system can be used to get Radio Data System (RDS) values of FM broadcast signals.

5. The FM signal spectrum can be viewed using the Android app.

6. Troubleshooting guide is provided in the SDRTouch app for using the Android SDR system.

Read more at:-https://electronicsforu.com/electronics-projects/software-defined-radio-with-android-smartphones

Saturday 22 June 2019

Fraunhofer DAB/DRM MultimediaPlayer


Providing the full potential of digital radio on smartphones, tablets and PCs via radio app

Exploiting the full potential of digital radio on smartphones, tablets or PC receivers is possible with the Fraunhofer DAB/DRM MultimediaPlayer radio app. The radio app fully supports the digital radio standards Digital Radio Mondiale (DRM) and DIGITALRADIO DAB+.

Along with providing radio programs in stereo and 5.1 surround sound, the Fraunhofer MultimediaPlayer radio app offers a wealth of added-value features, including the parallel transmission of album covers, text messages, weather forecasts and sports results, all of which are displayed directly onto the player. As these features are transmitted together with the digital radio programs they are available without internet connection and free of cost.

Moreover, connecting the player with additional media sources – eg. internet, telephone or navigation facilities – paves the way for the easy and intuitive operation of hybrid applications. For example, Deutschlandradio’s Journaline service has already finessed this concept by enabling its users to access online podcasts and providing studio contact details with just one click.

The transition between information stemming from the internet and information coming via broadcast is seamless. Both data streams come together on the MultimediaPlayer which enables the user to simply choose the desired information without having to locate its origin beforehand.

Wednesday 19 June 2019

Emergency Warning Functionality on DRM Digital Radio for Saving Lives


Six-hundred-and-seventeen (617) lakh people in the world were impacted by disasters in 2018. Extreme weather conditions accounted for majority of people affected by these disasters. Unfortunately, India is also being affected by disasters a number of times. But extreme weather conditions often come with a pre-warning phase. The questions is – Are we getting the most out of this time window to warn the public and save lives?

When disasters are about to strike, getting the message to everyone affected as quickly as possible and with all relevant information is of the utmost importance.
  • A typical early warning system should meet the following requirements:
  • Send notification to maximum number of people in the affected areas as promptly as possible;
  • Must cover large areas with very high reliability;
  • Must work when common information services and local services fail;
  • Make warnings available on devices that people use on daily basis;
  • Reach devices that are still operational, if electricity fails (i.e. radio sets and other devices with independent energy source);
  • Be as un-intrusive as possible for daily use;
  • Must be available and continuously on-air for the duration of the emergency;
  • Control of emergency notification and immediate access by authorities; and
  • Make emergency message available to widest possible audience, including the visually or hearing impaired. 

Technical solutions need to be able to meet specific requirements for this and ensure reliability even when the local infrastructure is down. In addition, everybody in a disaster area needs to be reachable, even people with impairments or visitors who do not speak the local language.

Unfortunately, internet, telephones, and electricity are generally the first causalities in disasters. Radio receivers have long been a core component of warning systems worldwide. Radio receivers can be battery, solar or wind-up powered; transmission infrastructure is both easily secured against power losses and can reach the affected area from outside. Thus radio transmissions are often the last way to maintain contact with people in heavily hit areas, when local power, cell, and TV towers are gone.

Radio is being used world over to provide emergency warnings but in the conventional analogue radios, the emergency program replaces the normal program, and radio listeners in the entire coverage area of the transmitter get only emergency program even if disaster is in a limited area. In disasters, it is of utmost importance that my radio receiver should automatically get tuned to the emergency program so that even if I am listening to a radio station, which is not broadcasting emergency program, still my receiver should get tuned to the emergency program automatically. Also, volume of my radio receiver should get increased, and if the receiver is in standby made it should get automatically switched on. But in analogue radios, there is no such provision to provide alert signaling and as such they cannot get automatically tuned to the emergency programs. Also analogue radios provide only audio programs and do not have any provision to provide text, which is very important to provide information in the local languages.

Emergency Warning Functionality (EWF) in the DRM digital radio standard, adopted by All India Radio (AIR), overcomes all the shortcomings of the analogue radio and has all the tools required for early warning dissemination.

When the alarm signal is triggered by the authorities, all running DRM receivers pick up the alarm signal from the currently tuned DRM service and switch to the emergency broadcast; all DRM receivers present the audio content of the emergency broadcast; all DRM receivers with a text screen, in addition, present text headlines (DRM text messages) plus detailed, multilingual information, and instructions (Journaline) for instant and interactive look-up by user, and turned-off receivers may switch on automatically. In addition, the volume is increased and the emergency state is visually indicated (e.g. through a flashing screen or LED). In an emergency, a DRM digital radio set can wake up its user and provide the required information. The same is true for cars and mobile phones: Alerts and information will reach you even if the car radio is off, or when your mobile phone is disconnected from the internet.

The emergency program via DRM can consist of the audio announcement (e.g., a quickly repeated headline in a single language), but can also be accompanied by text information based on its standardized Journaline service component, a core DRM element. The structured text feature allows users to look up relevant information on the digital radio’s screen much quickly and in more detail than what would be available over audio channels.

This enhanced information can include locations and descriptions of shelters sorted by region, contact details of public authorities, or general advice for before, during, and after the event. The information can be dynamically updated and enhanced by the disaster management authority at any time as the situation evolves. In addition, Journaline is designed to reach the hearing impaired, as well as travelers who do not speak the local language, through its multilingual support. The system also carries an exact description of the affected area to limit unwanted receiver switching.

On a technical level, implementing EWF into any DRM receiver is not complicated, because EWF is a combination of standard functionalities that need to be supported by any DRM digital radio receiver. It combines DRM’s alarm announcement and alternative frequency signaling and switching (AFS) with audio decoding and Journaline presentation.

There is very little manufacturers need to do for the digital receiver to be EWF compliant. Mainly, they just need to ensure the receiver is equipped with an automatic volume increase and visual alarm indication. To ensure that the automatic receiver wake-up functionality will be available on the widest possible set of DRM receivers in a country, regulators are encouraged to mandate this element in addition to general DRM EWF support as part of a policy for the receiver and automotive industry.

On the transmission side, all modern DRM encoder and multiplexer solutions today support EWF natively. To issue alarm signaling (typically triggered by a national authority) and to provide core information in audio and textual form to the DRM multiplexers for immediate playout, many countries rely on the commonly deployed Common Alerting Protocol (CAP), or its enhanced derivatives such as the Modular Warning System (MoWaS) standard in Germany.

Thirty-five high-power transmitters of AIR are already broadcasting programs simultaneously in analogue as well as in DRM digital. These DRM transmitters of AIR would cover over 50 percent population of the country on operation in pure DRM digital mode. Over 15 lakh cars on the Indian roads have line-fit DRM digital radios. This number is increasing day by day. Most of the automotive manufacturers in India are either already rolling out cars with DRM reception facility or have plans to incorporate the same. A number of Indian and foreign companies are also working to produce standalone DRM digital radios. An Indian firm has also developed a DRM Wi-Fi hot spot, which will enable a listener to receive DRM digital radio signals on any Wi-Fi enabled device – be it mobile phone, laptop, I-pad, desk top computer, or TV.

For using DRM digital radio network for disaster management in emergencies, the following four major steps are required:
  • Government decision to utilize DRM for dissemination of EWF;
  • Identification of coordinating agency;
  • Choice of language(s) and additional information to be provided; and
  • Firm communication to the receiver industry for full incorporation of EWF features.
AIR has already tested the EWF successfully, in coordination with National Disaster Management Authority (NDMA), on both the DRM transmitters installed in Delhi using CAP protocol. Decision by the Indian government to use DRM digital radios for providing emergency warning signals would go in a big way to provide timely information to disaster-affected people to save their valuable lives.

Source:-https://www.broadcastandcablesat.co.in/services/emergency-warning-functionality-on-drm-digital-radio-for-saving-lives/

Wednesday 12 June 2019

Audio source coding


With xHE-AAC, your DRM service sounds better than ever before, even at very low bit rates.
Useful bitrates for DRM30 range from 6.1 kbit/s (Mode D) to 34.8 kbit/s (Mode A) for a 10 kHz bandwidth (±5 kHz around the central frequency). It is possible to achieve bit rates up to 72 kbit/s (Mode A) by using a standard 20 kHz (±10 kHz) wide channel.[(For comparison, pure digital HD Radio can broadcast 20 kbit/s using channels 10 kHz wide and up to 60 kbit/s using 20 kHz channels.) Useful bitrate depends also on other parameters, such as:
  • desired robustness to errors (error coding)
  • power needed (modulation scheme)
  • robustness in regard to propagation conditions (multipath propagation, doppler effect), etc.
DRM system provides ability to switch depending on the strength of reception and perceived audio quality. It provides three kinds of audio codecs namely Advanced Audio Codec (AAC), Code Excited Linear Prediction (CELP) and Harmonic Vector Excitation Coding (HVXC), which vary in quality, bit rate requirement, and its application. CELP and HVXC are designed for speech-only services requiring lower bit rates, while AAC provides highest quality. DRM system provides low data rates at high quality by utilizing MPEG xHE-AAC and AAC with PS (Parametric Stereo) and SBR (Spectral Band Replication). The modulation technique and channel coding used are Quadrature Amplitude Modulation (QAM) and Coded Orthogonal Frequency-Division Multiplexing (COFDM) respectively. The DRM+ system is designed for use in any of the VHF Bands I, II and III, each containing its own channel raster7
.
When DRM was originally designed, it was clear that the most robust modes offered insufficient capacity for the then state-of-the-art audio coding format MPEG-4 HE-AAC (High Efficiency Advanced Audio Coding). Therefore, the standard launched with a choice of three different audio coding systems (source coding) depending on the bitrate:
  • MPEG-4 HE-AAC (High Efficiency Advanced Audio Coding). AAC is a perceptual coder suited for voice and music and the High Efficiency is an optional extension for reconstruction of high frequencies (SBR: spectral bandwidth replication) and stereo image (PS: Parametric Stereo). 24 kHz or 12 kHz sampling frequencies can be used for core AAC (no SBR) which correspond respectively to 48 kHz and 24 kHz when using SBR oversampling.
  • MPEG-4 CELP which is a parametric coder suited for voice only (vocoder) but that is robust to errors and needs a small bit rate.
  • MPEG-4 HVXC which is also a parametric coder for speech programs that uses an even smaller bitrate than CELP.
However, with the development of MPEG-4 xHE-AAC, which is an implementation of MPEG Unified Speech and Audio Coding, the DRM standard was updated and the two speech-only coding formats, CELP and HVXC, were replaced.
  • xHE-AAC (Extended HE-AAC), primarily developed by Fraunhofer IIS and the latest addition to the MPEG AAC codec family, bridges the gap between speech and audio coding. It provides consistently high-quality audio for all signal types, such as speech, music or mixed content, at all bit rates – starting as low as 6 kbit/s for mono and 12 kbit/s for stereo services, up to 500 kbit/s and above. This makes xHE-AAC the audio codec of choice for digital radio and adaptive streaming applications. It is a mandatory audio codec in Digital Radio Mondiale .
xHE-AAC-streaming services sound better than ever, even at low bit rates.
xHE-AAC for DRM 
DRM (Digital Radio Mondiale) is the first digital radio standard to adopt xHE-AAC.By now, the most recent addition to the AAC codec family is on the air in India: already, the first five major transmitter locations in India, two at Delhi, and one each at Bangalore, Pune, and Chennai have been upgraded with xHE-AAC-enabled DRM equipment by RFmondial with Fraunhofer technology components inside. In total, there are 39 transmitter locations (including 35 transmitters that form the domestic medium-wave network), which all are expected to receive this latest upgrade moving forward.  xHE-AAC makes it possible to provide much better, FM-like audio quality, as well as more programs in a single DRM transmission, up to three instead of one. The upgraded DRM encoder equipment also supports the provision of detailed textual information like current news, information, program schedules, traffic updates, and contact information via DRM’s Journaline advanced text service. Eventually, based on DRM’s emergency warning functionality (EWF)

Sunday 9 June 2019

Why Digital radio is less susceptible to noise and interference.


If the path from the transmitter to the receiver either has reflections or obstructions, we can get fading effects,it is doppler effect. In this case, the signal reaches the receiver from many different routes, each a copy of the original. Each of these rays has a slightly different delay and slightly different gain. The time delays result in phase shifts which added to main signal component (assuming there is one.) causes the signal to be degraded.Fading is big problem for signals. The signal is lost and demodulation must have a way of dealing with it. Fading is particular problem when the link path is changing, such as for a moving car or inside a building or in a populated urban area with tall building.

Digital radio is less susceptible to noise and interference, which can manifest itself as fade, hiss or crackle on FM radio. Digital radios don’t suffer in this way because they maintain reception quality up until the signal becomes unsustainably weak, whereas the reception quality of FM radios gets steadily worse as soon as the signal begins to weaken. This is particularly relevant to people using radios in cars because constant movement means signal strength is likely to vary it is doppler effect.

Coded orthogonal frequency division multiplexing Modulation is an essential component of terrestrial Broadcasting.COFDM signals are comprised of large no of closely spaced carriers ie frequency division multiplexing .These carriers have to be closely spaced for bandwidth efficiency but must be prevented from interfering with each other so it is important they are orthogonal .In this typical multipath condition a high proportion of these carriers may be notched out . Resulting in transmission errors so the transmitted signal must include powerful error coding codecs

COFDM Modulation was specifically designed to reduce the problems caused by multipath. The process takes I/P bit stream,divides it up into multiple parallel lower rate bit stream ,and modulates these on to a large number of individual carriers.The number of carriers can vary between few hundred to several thousand,depending on the transmission specification and design parameters of broadcast signal.These carriers are closely spaced in frequency and this would normally mean that adjacent carriers would interfere with each other .

COFDM system avoids self interference by making the use of fact that if carriers spacing-is reciprocal of symbol length it is possible to demodulate each carrier individually and ignore the contribution of its neighbor.Under this condition the carriers are said to be orthogonal to each other.Demodulation process is typically accomplished using fast Fourier transform.In order to minimize the determined effect of delayed echoes,each symbol is transmitted for a length of time equal to useful symbol period plus an additional Guard interval .

COFDM demodulator can work effectively with out being subject to inter symbol interference in both the frequency domain and the time domain. COFDM works well with echoes .This fact allows single frequency network.The final mechanism of multipath interference to be discussed is the Doppler shift.If receiver is moving itself or is in the presence of the moving object ,then reflected signal will have frequency shift on them . The amount of frequency shift that is acceptable is governed by the carriers spacing . systems which closely spaced carriers are more susceptible to problems caused by Doppler shift , which is requirement for in car receivers .

The modulation used for DRM is coded orthogonal frequency division multiplexing (COFDM), where every carrier is modulated with quadrature amplitude modulation (QAM) with a selectable error coding.The choice of transmission parameters depends on signal robustness wanted and propagation conditions. Transmission signal is affected by noise, interference, multipath wave propagation and Doppler effect.

It is possible to choose among several error coding schemes and several modulation patterns: 64-QAM, 16-QAM and 4-QAM. OFDM modulation has some parameters that must be adjusted depending on propagation conditions. This is the carrier spacing which will determine the robustness against Doppler effect (which cause frequencies offsets, spread: Doppler spread) and OFDM guard interval which determine robustness against multipath propagation (which cause delay offsets, spread: delay spread). The DRM consortium has determined four different profiles corresponding to typical propagation conditions:
  • A: Gaussian channel with very little multipath propagation and Doppler effect. This profile is suited for local or regional broadcasting.
  • B: multipath propagation channel. This mode is suited for medium range transmission. It is nowadays frequently used.
  • C: similar to mode B, but with better robustness to Doppler (more carrier spacing). This mode is suited for long distance transmission.
  • D: similar to mode B, but with a resistance to large delay spread and Doppler spread. This case exists with adverse propagation conditions on very long distance transmissions. The useful bit rate for this profile is decreased.
The trade-off between these profiles stands between robustness, resistance in regards to propagation conditions and useful bit rates for the service. This table presents some values depending on these profiles. The larger the carrier spacing, the more the system is resistant to Doppler effect (Doppler spread). The larger the guard interval, the greater the resistance to long multipath propagation errors (delay spread).The resulting low-bit rate digital information is modulated using COFDM. It can run in simulcast mode by switching between DRM and AM, and it is also prepared for linking to other alternatives

DRM has been tested successfully on shortwave, mediumwave (with 9 as well as 10 kHz channel spacing) and longwave.

Mode
OFDM carrier spacing (Hz)
Number of carriers
Symbol length (ms)
Guard interval length (ms)
Nb symbols per frame
9 kHz
10 kHz
18 kHz
20 kHz
A
41.66
204
228
412
460
26.66
2.66
15
B
46.88
182
206
366
410
26.66
5.33
15
C
68.18
-
138
-
280
20.00
5.33
20
D
107.14
-
88
-
178
16.66
7.33
24

Error coding

Error coding can be chosen to be more or less robust.
This table shows an example of useful bitrates depending on protection classes
  • OFDM propagation profiles (A or B)
  • carrier modulation (16QAM or 64QAM)
  • and channel bandwidth (9 or 10 kHz)
Bitrates, kbit/s
Protection class A (9 kHz) B (9 kHz) B (10 kHz) C (10 kHz) D (10 kHz)
64-QAM 16-QAM 16-QAM 64-QAM 16-QAM 64-QAM 16-QAM 64-QAM
0 19.6 7.6 8.7 17.4 6.8 13.7 4.5 9.1
1 23.5 10.2 11.6 20.9 9.1 16.4 6.0 10.9
2 27.8 - - 24.7 - 19.4 - 12.9
3 30.8 - - 27.4 - 21.5 - 14.3
The lower the protection class the higher the level of error correction.

Friday 7 June 2019

AIR Pune has organized a session to demonstrate operation of DRM receiver and share information of DRM on 06-06-2019






AIR Pune has organized a session to demonstrate operation of DRM receiver and share information of DRM on 06-06-2019 . Function started at 2.30 pm in conference room.Deputy director general Engg and head of office Shri Ashish Bhatnagar, deputy director programme Shri Gopal Autee, Smt Sangeeta Upadhye ADE, Shri Ashok kale ADE, All PEX, TREX, and senior announcers of AIR Pune were present.Shri Manoj Shaha ,AE, elaborated the operation of DRM Receiver also given information of live streaming of AIR Pune on internet and the concept of DRM Transmission 

DRM Receivers demonstrated to all program officer. Comparison between DRM reception and analog reception was demonstrated. Advantages of DRM were discussed and the queries of programme officers and staff were well adressed by Engg officers.Information was given regarding the channel broadcasted on Simulcast and full DRM transmission. Also brief information regarding journaline was given in the session.

Shri Ashish Bhatnagar,DDG AIR Pune also shared his views regarding DRM transmission and explained technical matters related to DRM Transmitter

Monday 3 June 2019

What’s Your Simulcasting Strategy?



 In a recent petition to the FCC in the United States, a Texan broadcasting corporation rightly points out that “all-digital systems represent the future of radio.” This is the premise of its request to allow the introduction of pure HD in the medium wave in the U.S. As some broadcasters are questioning the current performance and the limited testing of HD in this band and its reception quality and coverage, such a request has certainly opened a digital Pandora’s box. It has also shown that something better than the current simulcasting scenario (mainly used in the FM band, with its own interference issues) is needed.


“Simulcasting” is a bit like “digital” or “hybrid” and can have a lot of meanings and nuances. The word generally refers to broadcasting in analog and digital at the same time, whether in the VHF or AM bands (mainly medium wave, as simulcasting in shortwave could be a step too far and engineers do not really recommend it).

Simulcasting exists in pure digital. In a very broad sense, we could say that DAB can broadcast simultaneously up to 18 (different) programs covering the same area and using a chunk of 1.5 MHz of spectrum in Band III. Or DRM can broadcast up to three (different) audio programs and one data program using the spectrum occupied by an analog medium wave channel or half a FM channel (96 KHz) and in Bands I and III as well. Some broadcasters have taken the simulcasting route (same program in analog and digital) in the belief that it will deliver the same power and coverage in both modes — nonsense in physics. This would be a bit like sharing an apple between two brothers and hoping that each will enjoy the whole fruit.

Even if digital radio is less energy hungry than FM or AM (DRM for example only requires a maximum of 10% of the power needed for FM analog), simulcasting needs compromises simply because analog and digital carry audio differently. Simulcasting requires extra equipment, extra energy, if the same coverage is to be maintained, extra planning and extra care.

So why go for simulcasting then, at all? Simulcasting is a good way to introduce digital radio and the extra benefits related to audio quality, richness of content and data. India has taken this path with its 35 medium-wave transmitters that simulcast in analog and DRM, while slowly introducing pure digital DRM.

As digital transmitters are calibrated and receivers slowly emerge, ready to be bought by the listeners, simulcasting is a valid transition path.

In DRM, at least, one single transmitter can support broadcasting both an analog and a digital DRM signal side-by-side, or even where available in the band (this refers mainly to the VHF Band II). The extra costs of simulcasting dictate, though, that a switch off date needs to be set, as this concentrates the minds and efforts and does not stretch the project into uncertain times. And like so often, timing is everything.

There can be an abrupt switch off, like in Norway. There can be a transition, a voluntary switch to digital (medium wave) only, as it is on the discussion FCC agenda just now.Or there can be a consultation, a digital review, as recently announced in the United Kingdom. The British Digital Minister rightly considers that, due to the changes in technology and competitive landscape in the past five years, “the debate about the future digital transition program for radio has shifted.”

So, while switch off straight away or simulcasting seemed the best two possible scenarios, the situation looks a bit more complex with the addition of IP or broadband delivery and other platforms to the digital radio mix. After all, when a program is terrestrially broadcast and also streamed, we also have simulcasting.

This digital cocktail preoccupies many of the broadcasters, the politicians and especially the observers of the mysterious millennials or “snowflakes.” The figures are quite clearly in favor of terrestrial. In the U.K., online and apps deliver 11%, the channels on digital TV 5%, with DAB digital radio scoring about 40.4%, the result of the push and investment of almost three decades. In Australia FM is still supreme with 7.8 hours listening a week, AM 4.7 hours, digital radio 1.3 hours and online 1 hour (according to the research commissioned by the regulator in May 2018).

Is simulcasting then the dawn of digital radio? Or is it a permanent state of affairs paralyzing those afraid to lose a significant, though maybe declining analog audience, but very keen to chase new younger audiences and their new digital habits?

Simulcasting the same programs on both analog and digital only makes sense if analog cannot reach them (as it happens in parts of India and surely elsewhere). Maintaining the analog signal and adding the digital part immediately offers the chance to present the same channel but, at least in DRM, also bring new content on at least the two extra channels created in digital. These can be used for new content and can increase revenue opportunities while increasing competition. In this way simulcasting offers enhanced capacity to carry the same in analog and digital but also something new and better, more attractive that can prove the advantages of digital radio.

Simulcasting can stifle or enhance radio. In the U.S., leaving simulcasting and pitching for pure HD in AM is seen as a way of saving the valuable medium-wave band. There are other ways, too, as mentioned by Larry Todd, vice president of WRNJ Radio, in the article he wrote for Radio World on a solution to the AM Problem.

Simulcasting analog and digital radio signals is more than a technical issue. It is about creating new attractive content rather than just duplicating existing programs and formats. It is about accepting competition, opening the radio market and about a strong belief in radio and its digital terrestrial future.

If simulcasting is just buying time for an unidentified “better” hybrid future, digital radio will remain in limbo.

Source:-https://www.radioworld.com/columns-and-views/whats-your-simulcasting-strategy

Sunday 2 June 2019

Software for efficient implementation of drm radio receivers


Modern radio receivers for car and home entertainment contain more and more software. This enables the radio maker to support different radio standards on the same hardware platform. Updates or extensions become possib-le even in the very last stage of the development process.

The Fraunhofer IIS DRM Receiver Kit is the first DRM solu-tion providing radio manufacturers this flexible software option for their radio platforms.

Key Features

The DRM Receiver Kit from Fraunhofer IIS is a fully validated DRM solution for the automotive and consumer market. This innova-tive software radio approach allows terminal manufacturers to efficiently enhance their radio platform with the full range of the DRM feature set. It is a platform independent C-code ready for multiple baseband and service layer instances.

Fully compliant with the ETSI ES 201 980, the DRM Receiver Kit is able to decode a full DRM multiplex or only a subset to save computing power. With its flexible data interface, it can be easily combined with external applications. The API interface is adopt-able to the customers framework.

Basic feature set of the baseband processing:
  • Reception frequencies up to 240MHz
  • Automatic mode detection for DRM mode A-D
  • Full featured FAC, SDC, MSC decoding
  • 4,5kHz, 5kHz, 9kHz, 10kHz, 18kHz, 20kHz, 96kHz bandwidth
  • Optionally including DRM+ (Mode E)

Basic feature set for audio and data decoding (DRM profile):
  • MOT decoder in header and directory mode
  • Packet mode decoder, enhanced packet mode decoder
  • MPEG HE-AAC v2
  • MPEG xHE-AAC
  •  Legacy CELP and HVXC on demand 

Saturday 1 June 2019

Hyundai Mobis and DRM Consortium have collaborated to deploy DRM receiver and chip for Indian automotive market

Hyundai MOBIS produces core automotive components such as modules (chassis, cockpit, front-end-module) and many automotive parts. 

Hyundai Mobis and DRM Consortium have collaborated to deploy DRM receiver and chip for Indian automotive market.NXP Semiconductors and Hyundai Mobis have successfully completed the field trials of MOBIS DRM receivers and NXP chips designed in India. The chips and DRM receivers are now deployed in DRM-fitted car infotainment receivers in a recently launched vehicle in India.

DRM is a digital radio standard that has been deployed in emerging markets such as India. DRM provides FM-comparable or better audio quality on the AM radio band. Since AM radio covers more than 98% of the population in India and only 37% of listeners can currently receive the FM signal, DRM improves radio coverage and quality. This technology is affordable and provides additional data services such as traffic updates, natural disaster warnings and news.

The development and deployment was made possible by a regional collaboration between All India Radio, NXP Semiconductors, Hyundai Mobis and the DRM Consortium.