| 摘要 |
PURPOSE:To realize the measurement with high accuracy for the electric field near an antenna without giving any effect to the line at a mobile part, by compensating the value measured by a probe based on the measured value of the reference intermediate frequency signal which is reflected from an interruption switch. CONSTITUTION:When a breaker 16 is turned off, the reference intermediate frequenxy signal given from an oscillator 8 is reflected by the switch 16 to be extracted via a two-way coupler 15. Then the amplitude and the phase according to the loss of a line 13 or the change of the electric length, etc. are detected by an amplitude/ phase detector 20. Afterward, the breaker 16 is turned on, and the amplitude and the phase of the electric field of an antenna 1 which are converted into the intermediate frequency signal by a mixer 6 and caused by a probe 5 are detected by the 1st amplitude/phase detector 11. The value fo this detection is compensated by an operator 12 basing on the detection value of the detector 20. Accordingly the electric field distribution near an antenna is measured with high accuracy and without giving any effect to the change, etc. of the line at a mobile part. Thus the antenna directional pattern is accurately decided. |
