| 摘要 |
To measure the three components of the electrical field and to form the summation vector of the measured three components, a near-field probe is proposed, which has a cuboid metallic housing on the outer surfaces of which in each case an antenna element in the form of a monopole is attached at right angles. On one corner of the housing, an electrically insulated holding handle is mounted in the direction of the relevant space diagonal of the housing. In the interior of the housing, a device for conditioning and processing the measurement voltages at the bases of the antenna elements is attached which has a separate channel for each of the six antenna elements for conditioning the relevant measurement signal with respect to RF. Each channel comprises an antenna input stage, a range divider and a separating stage. In each case two conditioning channels allocated to one measurement plane (e.g. x plane) lead to balanced inputs of a common squaring stage which has an integrated mixer chip with quadratic amplifier characteristic for forming the product of the two channel signals at the input end, and thus for RF rectification. The output signals of the three squaring stages are added and amplified and then supplied to an indicating instrument which has a scale with quadratic division to reduce the amplified aggregate signal. The scale can be read through a cutout in one housing wall.
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