Accession Number:

AD0656890

Title:

APOLLO TELEMETRY FRAME SYNCHRONIZATION TECHNIQUES.

Descriptive Note:

Technical memo.,

Corporate Author:

JOHNS HOPKINS UNIV SILVER SPRING MD APPLIED PHYSICS LAB

Personal Author(s):

• Coleman,T. W.
• McIntyre,J. W.

Report Date:

1967-05-01

Pagination or Media Count:

71.0

Abstract:

An analysis has been made of data frame synchronization control for Apollo downlink telemetry. The basic objective was to determine the effects of varying the switch-controlled error tolerance thresholds of two types of existing operational equipment. Criteria for setting these error tolerance switches are presented. The criteria are established to control the average time spent in the acquisition and lock modes of the data decommutation process. Any choice of switch settings would be dependent upon the data quality and quantity requirements of a particular mission. Examples of switch setting criteria are given which depend upon maximum acceptable bit error rates based on assumed operational requirements. Author

Descriptors:

• (*TELEMETER SYSTEMS
• SYNCHRONIZATION(ELECTRONICS))
• SPACECRAFT
• CONTROL SYSTEMS
• SWITCHING CIRCUITS
• ERRORS
• PROBABILITY
• TABLES(DATA)

Subject Categories:

• Electricity and Magnetism
• Telemetry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE