Dab Radio

Posted on February 7, 2010 by greenstoneradio.
Categories: Uncategorized.

Digital Audio Broadcasting, or DAB, is a digital technology that is designed to broadcast radio stations to a wide audience.

Initial development of DAB technology began in the early 1980s in Germany and first DAB transmissions were made across the country in 1988. Key choices concerning the specifics of the technology to be used were made in 1990 and the complete protocol was finalized in 1993.

The United Kingdom was the first country to adopt DAB as a widespread radio broadcasting system. The first commercial DAB radio receivers went on sale during 1999 and by 2001 there were more than 50 DAB stations being broadcast across London. These first stations were either run by the BBC (British Broadcasting Corporation) or individual commercial ventures.

In 2006, approximately 500 million people worldwide were within coverage of DAB radio broadcasts but sales of DAB receivers were still limited to a handful of European countries. Around 1000 DAB radio stations were in operation around the world at this time.

One of the main objectives of developing DAB radio was to improve the overall sound quality of transmissions by achieving higher fidelity and more resistance to noise and interference.

On many of the early DAB systems however, a better quality of sound can be achieved via the established FM (Frequency Modulation) radio stations due to the relative inefficiency of the audio codec used for DAB broadcasting.

Despite this failure to improve sound quality there are many other benefits inherent to the DBAB system. DAB radio stations are more bandwidth efficient than their analogue counterparts, so more stations can be made available and broadcasting costs are lower.

DAB radio transmitters also have the capability to automatically tune to a particular station chosen from a list, as well as receiving textual information about the broadcast, such as the title of the current song or traffic information for the station.

A newer version of DAB, termed DAB+, was made available in 2006 with the adoption of a new audio codec. This upgrade has the primary goal of achieving greater sound quality for DAB radio transmissions.

Social Network Analysis

Posted on January 13, 2010 by greenstoneradio.
Categories: Social Network Analysis.

The aim of Social Network Analysis is to visualise and understand the relationships between people and then act upon these findings. People within the network are referred to as nodes, relationships between people are referred to as ties, while information about the node are node attributes.

Social Network Analysis provides a visualise map of where crucial information and knowledge is flowing within the business. For example, suppose you want to analyse who is talking to who and how frequently this collaboration happens in a research project. Using a social network analysis survey to ask the question “Who do you collaborate with?” across the sample of users will provide you with the data to create the network map. The questions typically use a Likert Scale to gauge how often collaboration occurs:

1. Very Frequently
2. Frequently
3. Occasionally
4. Rarely
5. Very Rarely
6. Never

The data collected from all respondents is then transferred to a matrix. Where people are labelled as nodes and the strength of the relationship between nodes is labelled 1 to 6. This marix can then be analysed using UCINET or NetDraw. Both software programs are typically used for Social Network Analysis and both allow statistical analysis. However, UCINET itself does not visualise the network, NetDraw is bundled within UCINET and provides that capability.

Social Network Analysis is interested in the whole of the network and not just the individual’s ties and links. Taking this holistic view or Systems Engineering approach, allows the structure of the ties and how they interact in terms of strengths (derived from the Likert Scale) to be analysed.

Once you have your social network analysis data then it can be used to visualise the social relationships and identify collaborative groups, cliques of people, areas of poor collaboration and personal networks (ego networks). This information is very powerful and can help to identify where collaboration, knowledge management research and Information Management can help. Powerful knowledge sharing people often bridge networks together and these are called knowledge brokers. When working in teams you would assume that the knowledge broker would be the team leader, but you may also discover that a team members has a wider collaborative network.

Radio Broadcasting

Posted on November 25, 2009 by greenstoneradio.
Categories: Radio, Radio broadcasting.

Radio broadcasting is a means of transmitting audio signals via the air as radio waves. These radio waves travel from a transmitter to an antenna and from there are sent to a receiving device to be interpreted.

Radio waves are a form of electromagnetic radiation with a very high frequency. They are invisible to the human eye and sit above infrared waves in the electromagnetic spectrum. They provide a relatively simple and inexpensive way to transmit signals to wide audiences.

Whilst radio stations are commonly known as public systems there are also many stations that exist for non-broadcast purposes, such as base stations used by the emergency services, dispatch stations used by truck and taxi services, amateur radio stations and emergency broadcast systems.

The two primary types of radio station are AM and FM stations.

AM radio stations were the earliest wide-scale broadcasting systems to be developed. AM stations use amplitude modulation to change the radio carrier signal so that it can be interpreted by the listener.

A key advantage of AM radio stations is that the signal being transmitted is relatively unsophisticated, and as such it can be detected and decoded with basic equipment. However, this simple signal is vulnerable to interference by bad weather.

FM radio stations use frequency modulation to alter the radio carrier signal and broadcast a message. FM stations broadcast in the VHF (Very High Frequency) range of airwaves in the frequency range of 88 MHz to 108 MHz.

FM radio was invented in the 1930s by Edwin Armstrong with the sole purpose of solving the interference problems inherent in AM radio. FM radio is almost immune to this interference and has also achieved greater signal clarity by spacing radio stations further apart than AM stations.

The emergence of the Internet has prompted radio stations to broadcast online. Since the 1990s radio stations have been broadcasting on the Internet where they do not suffer from the licensing restrictions applied to other stations, and there is no need to setup air transmission equipment to be able to broadcast to the world.

Radio technology

Posted on October 3, 2009 by greenstoneradio.
Categories: Radio, radio technology.

Radio communication is a widely used form of communication that takes advantages of the characteristics of radio waves to transfer messages across wide distances. Radio messages are sent from a radio transmitter and are received by an antenna which sends them to a receiving device.
The most popular usage of radio communications today is radio broadcasting – an audio broadcasting service widely used by listeners for music and broadcast conversations. Other types of communications sent via radio waves include Morse code, and more recently DAB, or Digital Audio Broadcasting.

The two most common forms of radio broadcast include AM and FM; the two techniques used to broadcast commercial radio stations. Radio waves can also be sent and received via citizens band radio (CB radio) or even transmitted via satellites.

The fundamental idea behind broadcasting radio communications is to transmit a carrier signal which can be received by a correctly tuned receiver and then to vary that carrier signal according to the message you want to send.

AM Radio

A.M. stands for amplitude modulation and was the original method used to broadcast radio stations. It involves changing the amplitude of the carrier signal to send a message. It is a very simple system that does not require a lot of expensive equipment to receive a signal.

AM radio signals are subject to interference by EMI, or Electromagnetic interference. This is most notable to listeners during weather events such as lightning storms.

FM Radio

F.M. stands for frequency modulation and involves varying the frequency of the carrier signal to transmit a signal. This technique is used in the VHF, or “Very High Frequency”, range of airwaves.

FM Radio allows broadcasts to be made with much less interference than AM signals, and by spacing FM stations further apart they are less likely to interfere with each other. The range of an FM broadcast is not as great as an AM broadcast so they are more suitable for local radio stations.

Radio Information

Posted on September 7, 2009 by greenstoneradio.
Categories: Radio.

Green Stone Radio was a women’s radio show run from New York. With high profile support the radio show broadcast on 7 affiliate radio shows and provided women focused humour and information.

The station closed in 2008 after operating for less than a year.