Road Network Operations
& Intelligent Transport Systems
A guide for practitioners!
Pre-trip and en-route radio travel advice and guidance are particularly hard to disentangle. (See En-Route Information, Radio) The key issues with the distribution of traveller information by radio and television are selecting which information is disseminated- and targeting it at the correct audience.
Television is used to deliver traffic and travel information via:
In the internet age, generally the content for text-based travel information services is identical to that provided for internet traffic information - but its presentation may be different depening on the bandwidth available for information broadcast and transmission/retrieval.
When considering broadcasting TV bulletins, the content is generally constrained by the length of time slot available. Traffic and travel bulletins are often presented before and during key commuter times - and focus on planned and unplanned events with significant impacts. When considering TV bulletins it is important to take into account that traffic and travel items of wider interest, may have longer air times impacting so how these traffic and travel segments are put together.
The key to providing the correct content for bulletins is being able to clearly categorise traffic and travel incidents and effectively scripting the traffic broadcast - to create an interesting and behaviour changing travel news item. Specialist companies exist in most mature markets to assist with traffic news collation and scripting of broadcast items for radio and TV.
Pre-trip traffic and travel information delivered by Radio can be categorised as :
Dedicated traffic internet radio services are radio services which can be played by running an application in an internet browser or on specific internet radio hardware. These radio broadcasts consist of a looped programme of short duration containing significant traffic (planned and unplanned) incident information. A good example is the The UK’s Traffic Scotland service.
Internet radio services includes a codec - to code/decode the radio transmission, which is streamed over the internet. Various audio codecs are employed, although the Internet Media Device Alliancec is trying to standardise these and has published the IMDA Automotive Profile 1 - which specifies requirements for in-car internet radios including the transport layer and codecs to be used.
Traffic Information is also presented in conventional radio programmes - and is most often heard on the approach to, and during, peak commuting times. These broadcasts are contained as a segment, often as an add-on to news broadcasts - in a similar way to weather forecasts - and this applies to both internet radio, DAB and analogue broadcasts. The key requirement is for the travel bulletin to be focussed on the needs of the audience - and, in the same way as TV, needs to be interesting to all listeners (as far as practicable). The most severe incidents with the greatest impact should be the highest priority for broadcast. Traffic incident severity and impact should be determined and associated with the incident in such in a way that enables multiple reuse of the information.
Traffic information can also be distributed as a non-audio data stream (over radio). (See En-route Information)
Internet Radio
It is important to consider that the listener is unlikely to want to listen endlessly to Internet Traffic Radio - so broadcasts should be relatively short and regularly repeated to maximise their value to listeners.
Traffic/Travel Radio Bulletins
The key requirement for bulletins is that they are focussed on the needs of the audience, and - in the same way as TV - they need to be interesting to all listeners (as far as practicable). The most severe incidents with the greatest impact should be the highest priority for broadcast.
A lot of work has been undertaken to standardise the categorisation of events - such as the Alert C standard ISO 14819:2013 (parts 1 and 2) which defines event categorisation for RDS-TMC, and also the Datex 2 information exchange standard which is primarily for Transport Management Centre to Transport Management Centre communications. (See Network Monitoring)
For FM analogue radio - overlays for traffic announcements and definition of programmes containing traffic information are defined by the Radio Data System (RDS) components Extended Other Networks (EON), Traffic Announcements (TA) and Traffic Programmes (TP) for which more information is available on the RDS Forum.
Structuring and prioritising traffic and travel event information is the next issue to address as a key requirement - making consistent data dissemination a much easier prospect.