Automation in operation
On arriving at site, the vehicle can be readied for transmission. The required satellite is selected from a menu list on the control panel, and the GPS unit and the flux-gate compass feed the positional information of the uplink to the antenna control system. From this information, the control system can calculate the required antenna azimuth and elevation for the selected satellite.
Under control of the automated acquisition system, which is activated by a single button press, the antenna is raised from its lowered (park) position to a predetermined nominal elevation. It then rotates to the satellite’s azimuth, and elevates to the calculated elevation angle.
Some systems go one step further in sophistication, and use a known strong signal from the satellite to determine the correcting pointing angle by calculating the offset in azimuth and elevation from this known signal. The antenna controller, having used the GPs and flux-gate compass to aim the motorized antenna, then uses a control voltage derived from this known ‘beacon’ signal to ‘auto peak’ the antenna. On finding the ‘beacon’ signal, the control system fine tunes the antenna in azimuth and elevation (by jogging it left, right, up and down) to optimise the signal level from the beacon, ensuring that the antenna is accurately pointed.
Advantages and disadvantages of automation
Such a system has the undeniable advantage that technology can replace the highly tuned skills of a good uplink operator in finding the satellite. Staff with lesser technical skills are just as able to press the button to set the system in motion. This, combined with other technical functions that could be automated or pre-programmed in the operation of an uplink, could very well allow the use of journalists or any other spare pair of hands to operate the uplink – though the style of operation may be subject to a satellite operator restriction.
However, one must consider that the typical SNG system is an already sophisticated set of equipment, and the addition of an automated system for finding the satellite is ‘just another thing to go wrong’. If the system fails to find the satellite, it could be anyone of a number of processes that have failed. If such a system is used by an experienced uplink operator to save time, then if it fails, the satellite can still be found by manual methods, and the antenna correctly aligned. But in the hands of an unskilled operator, the transmission will be lost.
Its use is perhaps best seen on a small journalist-operated vehicle, which has a relatively simple function and usage.
Fully remote operation
This is an extension of the automated acquisition system, to a level where the entire uplink is remotely controlled. It has been implemented both on vehicles and on some flyaway systems, where remote control can be used once the antenna has been aligned manually with some additional ‘pointing aids’ for the non-technical operator.
The remote control package allows control of all the key operational parameters by a separate communications channel. This channel can be provided by a plain old telephone service (POTS), an Inmarsat satphone, or even a separate satellite channel that is activated via the antenna once it is correctly aligned.
The level of control can be relatively sophisticated, but as a basic minimum it will control the digital encoder, modulator and HPA.
However, as with the automatic acquisition systems, a failure of the system can be due to any number of reasons, and therefore there is a compromise that has to be accepted if opting for this mode of operation. Not many news organizations would want to deploy such a system in the hands of a nontechnical operator on a ‘big story’, and if the use of such a system is going to be constrained by the type of story it can be used on, it can be argued that it is a false economy.
It may seem here that we are debating whether someone whose primary job is not a technical one – e.g. a journalist – is capable of operating an SNG uplink with the different automated controls described. That is not the issue – it is more whether if, for example, a journalist is trying to do other jobs as well as their own, something will suffer. Newsgathering is not a serial process, i.e. jobs and tasks that have to be done do not concatenate neatly together. There are task overlaps on the timeline of reporting a story, and some even run directly in parallel. At times, it is not ‘a matter of many hands make light work’, but that many hands make it happen – on air and on time. On most stories, the journalist is busy simply keeping up with the story. On rapidly breaking events the requirement to repeatedly go ‘live’ for a string of different outlets can mean that the journalist is no longer effectively reporting the story as it carries on developing and unfolding, as they are still stuck in front of the camera reporting what has become ‘old’ news.