Study of delay instabilities within a Two-Way Satellite Time and Frequency Transfer earth station
被引:0
作者:
Shemar, Setnam L.
论文数: 0引用数: 0
h-index: 0
机构:
Natl Physical Lab, Middlesex, United KingdomNatl Physical Lab, Middlesex, United Kingdom
Shemar, Setnam L.
[1
]
Davis, John A.
论文数: 0引用数: 0
h-index: 0
机构:
Natl Physical Lab, Middlesex, United KingdomNatl Physical Lab, Middlesex, United Kingdom
Davis, John A.
[1
]
机构:
[1] Natl Physical Lab, Middlesex, United Kingdom
来源:
Proceedings of the Annual IEEE International Frequency Control Symposium
|
1999年
/
1卷
关键词:
Modems - Satellite communication systems - Time measurement;
D O I:
暂无
中图分类号:
学科分类号:
摘要:
The accuracy of the Two-Way Time and Frequency Transfer (TWSTFT) technique has been shown to be limited by propagation delay instabilities present in the earth station hardware. In this paper the National Physical Laboratory (NPL) has investigated a scheme for reducing delay instabilities in order to improve the accuracy of its time and frequency transfer. Tests show that cables propagating signals at 70 MHz or L-band have much lower temperature coefficients than cables propagating at Ku-band when measured with a TWSTFT modem. A scheme for improving earth station stability by propagating signals through cables at 70-MHz or L-band wherever possible has been investigated here. It is found that lower temperature coefficients are possible by adopting this scheme. Comparisons are also presented with tests carried out using a higher chip rate.