Observations of Argos Performance

Abstract

An Argos 32-byte message of known content has been transmitted over a 68-day period from a site located at Scripps Institution of Oceanography. The statistical analysis agrees with Service Argos. Due to sparse satellite coverage, only 6% of all transmitted messages are received. Of messages acquired, 9% contain at least one bit error. Error characteristics suggest the occurrence of noise bursts, rather than single-bit random errors. The low probability of seeing a satellite requires transmitting over many hours to ensure a single satellite reception. For such a long transmit duration, it is most efficient to send the same message infrequently (i.e., every 10 min), thus minimizing power consumption. This allows many unique messages to be interleaved, optimizing total information received in the smallest time frame.