JP2009025059A5

JP2009025059A5 -

Info

Publication number: JP2009025059A5
Application number: JP2007186444A
Authority: JP
Filing date: 2007-07-18
Publication date: 2010-06-17

Claims

A turntable capable of mounting and rotating the device under test in an EMI measurement anechoic chamber that blocks radio waves from the outside, and two types of radio waves radiated from the device under test having different frequency bands Two types of antennas for receiving radio waves are arranged, and outside the anechoic chamber, an EMI measuring device that performs EMI measurement based on a received signal from the antenna, and a measurement control that controls the entire EMI measurement Install the equipment,
An EMI measurement system that simultaneously performs EMI measurements in two frequency bands with the two types of antennas while rotating the turntable under the control of the measurement control device;
Of the two kinds of antennas, one antenna and MH _Z band antenna for measuring 30MH _{_Z} ~1GH _Z, as the other GH _Z band antenna for measuring the frequency bands above 1GH _Z antennas, separate The two antennas are arranged at 90 ° with respect to the device under test so as to suppress the influence of mutual radio wave reflection. An EMI measurement system, which is configured so as to be installed in a EMI measurement system.

The EMI measuring instrument is composed of at least two units,
2. The EMI measurement system according to claim 1, wherein the MH _Z band antenna and the GH _Z band antenna are individually connected to dedicated EMI measuring devices installed outside the anechoic chamber, respectively.

When the MH _Z band antenna is set in the horizontal direction, the GH _Z band antenna is set in the vertical direction, and when the MH _Z band antenna is set in the vertical direction, the GH _Z band antenna is set in the horizontal direction. The EMI measurement system according to claim 1, wherein both antennas are set to different polarizations to prevent a reflected wave from entering another antenna.

When the height of the MH _Z band antenna and the GH _Z band antenna is set by the antenna lifting platform, the height of both antennas is set to a different height so that the reflected wave enters the other antenna. The EMI measurement system according to claim 1, which is prevented.

A turntable capable of mounting and rotating the device under test in an EMI measurement anechoic chamber that blocks radio waves from the outside, and two types of radio waves radiated from the device under test having different frequency bands An EMI measuring device that performs EMI measurement based on a received signal from the antenna and a measurement control device that controls the entire EMI measurement are installed outside the anechoic chamber. ,
An EMI measurement method for simultaneously performing EMI measurement in two types of frequency bands with different frequencies using the two types of antennas while rotating the turntable under the control of the measurement control device,
A first procedure for setting the antenna lift for the MH _Z antenna and the antenna lift for the GH _Z antenna to antenna heights suitable for the respective frequencies under the control of the measurement control device;
A second procedure for setting the EMI measuring device connected to each antenna to a data writing state when the first procedure is completed;
When the second procedure is finished, the turntable is rotated, and when the rotation is finished, a third procedure for ending data writing of each EMI measuring device;
An EMI measurement method, wherein EMI measurement is performed by executing a fourth procedure for capturing measured data when the third procedure is completed.

MH _{Z Z} When the band antenna is vertically polarized, the MH _{Z Z} The height of the band antenna is set to 1 m and the GH _{Z Z} The EMI measurement system according to claim 3 or 4, wherein the band antenna is set to a height of 1.5 m as a horizontally polarized wave.