A man charged with stalking his ex-girlfriend by attaching a global positioning system to her car was sentenced to 16 months in state prison, prosecutors said. Ara Gabrielyan, 33, of Glendale, was sentenced Friday after pleading no contest to one count of stalking and two counts of making criminal threats, said Deputy District Attorney Debra Archuleta. Authorities contended that Gabrielyan attached a cell phone to the woman’s car on Aug. 16 with a motion switch that turned on when the car moved, transmitting a signal each minute to a satellite. Information was then sent to a Web site that allowed Gabrielyan to monitor the woman’s location.