摘要 |
The present invention relates to the problem of calibrating an antenna system (23) comprising an electrically controlled antenna (25) using a test antenna (45) arranged near the electrically controlled antenna, with the possibility of calibrating during operation, when disturbing reflections or other unknown signal influences are present when signals are transmitted between the test antenna and the electrically controlled antenna or between the electrically controlled antenna and the test antenna. The electrically controlled antenna comprises a number of modules (27-(1-N)) having means (91-(1-N)) for controlling the complex amplification of the modules. Each module is arranged with a commandable reference mode at reception and/or transmission. The antenna system is calibrated for reception and transmission, respectively, by transmitting test signals between the test antenna and the electrically controlled antenna and/or by transmitting test signals between the electrically controlled antenna and the test antenna, the effect of the unknown signal influence being eliminated by utilization of the reference modes at reception and/or transmission. |