Abstract: Inordertoaccomplishaccuratemeasurementofintersatelliteclockerrorandtransferoftimeandfrequency,theequipmentdelayonthegroundareusuallyrequiredtobecalibrated.Withtheagingofequipmentandthechangeofenvironmenttemperature,thedelayofsendreceivesignalwilldeviatethestandardization.Byusingpseudorandomcodecorrelationmeasurement,combiningwiththetimedivisionearlydelaypseudorandomcodephasealternationmodulationtechnologyandenvelopetechnology,aninorbitchanneldelayselfcalibrationmethodwasproposed.Bydesigningaproperclosedloop,thesendreceivechanneldelaycanbecalibratedinrealtimewithoutinfluencingthenormalcommunication.Theresultsindicatethatthedelaymeasurementprecisionofthismethodreachessubnanosecondlevel.

Key words: channeldelay, inorbitmeasurement, realtimecalibration, pseudorandomcodemeasurement, envelopedemodulation