1.JRC JMA-9900 series ARPA/Radar is developed to enhance the radar performance, user-friendly operation and visibility, which meet the performance standards of radar, ARPA and AIS information indication, which are specified in IMO. The JMA- 9900 main functions include; sea and rain/snow clutter suppression, sensitivity adjustment, interference reflector, bearing and range measurement using a trackball, fixed/variable range markers and electronic bearing line, ARPA, and AIS information function. The software-based digital signal processing of JMA-9900 series radar will provide a superior visibility with automatic control of gain, tune, anti-sea-clutter and anti-rain-clutter, which are adjusted for suitable radar condition. Furthermore, the enhanced echo-image processing will provide stable target- tracking condition with reducing target loss and transfer to close-by another target. The 23.1-inch LCD display has dimmer that can dim up to approximately 1% of the brightness, making it possible to use the radar at dark conditions during the night. Full inter-switching option up to 4 radars. This means that when 4 radars are mounted, any radar can be operated from any of the displays using external inter-switch. 2 Radar Inter- switching is also option component available for built-in. Basic operations and major functions can be operated with the fewest number of carefully chosen direct keys. Particularly, the function that will be frequently accessed is capable to be given to user key. The trackball and on-screen-buttons are available for quick access to the function control desired. The optical sensor of trackball eliminates false movement from ship’s vibration or rolling.