access subsystem

acquisition tracking subsystem

adaptive subsystem

address display subsystem

administration subsystem

Advances to IP Multimedia Subsystem (A-IMS)

Agro-meteorological disasters analysis subsystem

Aircraft Subsystem

Alarm Subsystem

analog computer subsystem

Antenna Control Subsystem

Argon production subsystem

Argon recovery subsystem

asphalt emulsion handling subsystem

ASU subsystem

AT winchester disk subsystem

Audio Vedio Subsystem

Automated guided vehicles subsystem

back load operation computer subsystem

backbone subsystem