AIS units for small charter fleet:

AIS (or Automatic Identification System A or B ) is a international transponder system for ships intending to increase the safety at sea world wide.

It operates in the VHF band. The two frequencies used worldwide are 161.975 and 162.025 MHz (channels 87B and 88B, or AIS1 and AIS2). The signal is transmitted via external VHF antenna and has the reach of normal VHF signal in line of sight.

An AIS transmitter regularly transmits the ship's position, heading, speed and MMSI (the unique maritime identification number). This data is received by ships in the vicinity or land stations.

The data can be plotted automatically on a digital map or radar screen. Several computer programs have been created for use with AIS data.

Some programs such as ShipPlotter and Gnuais use a computer to  demodulate the raw audio from a modified  marine VHF radiotelephone, tuned to the AIS frequencies.

The data can be displayed with charting programs as OpenCPN which is a Chart-plotter and GPS Navigation Software.

This would allow the land base office to keep track of each of their ships, their speed and location and estimated time of arrival at the dock, as well as the possibility of keeping a watchful eye over them in case they come of course.

Till recently AIS equipment was cost-prohibitive for smaller companies and did not reach its recognition but stayed in service for the big commercial fleet. 

With Dez. 2014 USCG AIS rules changed

With the AIS B system aimed at lighter commercial and leisure markets new products reach the market like the GPA-33

The GPA-33 is a 4.3" color LCD display AIS B transponder combo with GPS navigator in a small form factor like the Furuno GP-33 GPS it can be top mounted or flush mounted.

With a price of approximately 500,- per unit it should allow even small charter companies to equip their fleet.

At the base office you can either buy your own MarineGadget Radar - AIS Receiver or partner with http://www.vesseltracker.com/en/Home.html and use your existing infrastructure to build the worlds AIS tracking system

as in December 2004, the International Maritime Organization IMO 's Maritime Safety Committee condemned the Internet publication of AIS data as follows:

In relation to the issue of freely available automatic identification system (AIS)-generated ship data on the world-wide web, the publication on the world-wide web or elsewhere of AIS data transmitted by ships could be detrimental to the safety and security of ships and port facilities and was undermining the efforts of the Organization and its Member States to enhance the safety of navigation and security in the international maritime transport sector.

The softwear from OpenCPN is free of charge as are the NOA charts for your area.

Ship Station License from the FCC