CONTENTS

�1���� Introduction������
�2���� Design basis of digital system�������
������� 2.1���� System concept and application aspects�����
������� 2.2���� Voice coding techniques����
������� 2.3���� Modulation techniques�������
������� 2.4���� FEC techniques�����
������� 2.5��� �Standard B design example
�3���� Low G/T, data only, system concept (Standard C)�����������
�4���� Link budget considerations�����������
������� 4.1���� Multipath fading characteristics�������
������� 4.2���� Pointing/tracking error characteristics���������
������� 4.3���� Link budget examples��������
�5���� Advanced areas of system design�
Annex 1 - Performance characteristics of a digital voice-grade ship earth station����
�1���� System design���
�2���� Results of field experiment [Yasuda et al., 1987]��
Annex 2 - Performance of an experimental low G/T ship earth station����
�1���� Introduction������
Annex 3 - Enhanced group call system����
�1���� Introduction������
�2���� System description�����������
�3���� Link budget
�4���� Addressing techniques�����
�5���� Summary���
Annex 4 - Forward error control (FEC) as a means of multipath fading compensation����
Annex 5 - Inmarsat Standard C communications system����
�1���� Introduction������
������� 1.1���� Briefly the Standard C system is described as follows:��������
������� 1.2���� These techniques permit the following applications to be carried:�����
�2���� Design implications����������
�3���� Link budgets�����
�4���� Signal processing system��
������� 4.1���� Signal processing features��
������� 4.2���� Signal processing effects���� �����