Removing barriers to wider use of AIS

AIS, or Automatic Identification System, is used universally by the maritime industry to provide safety at sea and aids to navigation. Class B devices are intended to be used by non-SOLAS (Safety to Life at Sea) vessels, to provide identification and location data to vessels in the receiving area. Class B devices implement the CSTDMA, or Carrier Sense Time-Division-Multiple-Access modulation scheme, which involves ‘listening’ for an available time slot before transmitting.

The AIS Class B CSTDMA protocol is complex, forming a major part of the device’s design and its ability to conform to the applicable EN/IEC standards. Most notably, all Class B transponders must meet the requirements of the IEC 62287-1 standard, which governs Spectrum Usage and Access to Emergency Services. The SCT7033 is IEC 62287-1 compatible and ITU-R M.1371-5 compliant, which covers the technical characteristics for an AIS system using TDMA in the VHF maritime mobile frequency band.

By embedding the protocol stack alongside the processor, engineers have instant access to a fully compliant platform for AIS Class B transponder development. Using the SCT7033 as the basis for new product development enables significantly easier design and certification processes.

“The SCT7033 delivers a faster time to market, particularly for engineering teams with no previous experience of developing devices aimed at AIS,” commented David Brooke, Product Manager, CML Microcircuits. “As the protocol is provided with the device, embedded with the processor, engineers can focus on the system level features and adding their own differentiation, rather than developing a standard protocol.”

CML is a leading supplier to the marine industry, having a wide product portfolio aimed at AIS and other forms of communication systems. The SCT7033 is fully supported by CML’s engineering team and by the complementary products CML offers, such as baseband processors, frequency synthesisers and VCOs. The SCT7033 features all necessary interfaces for system design, including a C-BUS interface, SPI port, USB and UART interfaces and LED driver, as well as GPIO.

The SCT7033 is compatible with the CML DE70322TC AIS Class B Reference Design. A GUI is provided to enable production line configuration, such as parameter set-up and adjustment, the Mobile Maritime Service Indicator (MMSI) of other parameters specific to the device or its vessel.