During 2003 the IEN-PTB Two-Way Satellite Time and Frequency Transfer (TWSTFT) link was calibrated using a portable reference station. The calibration activity was conducted in the framework of the Galileo System Test Bed Version 1 (GSTB V1), under a contract with Joanneum Research G.m.b.H. (Austria). The calibration constant was determined with an uncertainty lower than 1 ns. Only few months after the calibration, the satellite provider moved the TWSTFT service to a different satellite; this caused changes non-reciprocal delays of the link (Sagnac and earth stations delays) and the calibration constant had to be re-evaluated. A recalculation of the Sagnac delays is presented together with a re-evaluation of earth stations delays with different measurements techniques.

A silicon integrated LNA for WCDMA cellular infrastructure applications, e.g. base stations will be demonstrated. The LNA is designed for the 1.92-1.98GHz band and reaches a 0.7dB NF at 27 o C and 1.1 at 65 o C. The output IP3 is +40dBm at 27 o C and +37dBm at 65 o C while having input and output return loss better than 20dB. A bypass mode and variable attenuation is also provided to cope with large input signals. The two-die MMIC is packaged on a single laminate. The total solution consumes a maximum of 197mA from a 5V supply.

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For a decade and a half GPS Common-View time transfer has greatly sewed the needs of primary timing laboratories for regular intercomparisons of remote atomic clocks. However, GPS as a oneway technique has natural limits and may not meet all chulollenges of the comparison of the coming new generations of atomic clocks. no-Way Satellite Time and Frequency nansfer (WSTFT) is a promising technique which may successfiUy complement GPS. For two years, regular WSTFT's have been performed between eighf laboratories situated in both Europe and North America, using INTELSAT satellites. This has enabled an extensive direct comparison to be mcrde behveen these two high performance time-transfer methods. The performance of the TWSTFT and GPS Common-View methods are compared over a number of time-transfer links. These links use a variety oftime-transfer hardware and atomic clocks and have baselines of substantially different lengths. The relative merits of the two time-transfer systems are discussed.

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