Controlled environment radio test apparatus and method

• US 6,088,582 A
• Filed: 07/16/1997
• Issued: 07/11/2000
• Est. Priority Date: 07/16/1997
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Canora, Frank James, Gaucher, Brian Paul, Flint, Ephraim Bemis
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Assistant Examiner(s): Bhattacharya, Sam
• Application Number:
  US08/895,167
• Time in Patent Office: 1,091 Days
• Field of Search: 455/67.4, 455/67.7, 455/115, 455/226.1, 455/423, 379/1, 379/21, 379/27, 379/29
• US Class Current: 455/226.1
• CPC Class Codes: G01R 29/0821 rooms and test sites therefor, e.g. anechoic chambers, open field sites or TEM cells for testing antennas G01R29/105
• CPC Class Codes: H04B 1/08 Constructional details, e.g. cabinet
• CPC Class Codes: H04B 17/0085 using test signal generators
• CPC Class Codes: H04B 17/309 Measuring or estimating channel quality parameters
• CPC Class Codes: H04B 17/391 Modelling the propagation channel

Abstract

A controlled environment radio test apparatus includes first and second chambers for receiving respective first and second radio devices therein. The chambers are sized in proportion to an operational frequency of the radio devices to be tested. A signal-carrying conductor is coupled to the first and second chambers to carry a radio signal therebetween. A signal control device is connected to the radio test apparatus and configured for adjustably introducing selected signal impairments into the radio signal in order to controllably impair the radio signal. An output coupler may be provided for monitoring the effect of the signal impairments on the radio signal. An input coupler may be provided for introducing one or more perturbing signals into the radio signal. The first chamber is adapted so that transmission control inputs can be provided to the first radio device and the second chamber is adapted so that reception monitoring outputs can be received from the second radio device. The first chamber may be further adapted so that auxiliary input and output signals are provided to and received from the first chamber.

Claims

1. A controlled environment radio test apparatus, comprising:

a first chamber for receiving a first radio device therein;

a second chamber for receiving a second radio device therein;

said first and second chambers being sized in proportion to an operational frequency of said first and second radio devices to be tested;

a signal-carrying conductor coupled to said first and second chambers to carry a radio signal transmitted by said first radio device for reception by said second radio device;

a signal control device connected to said radio test apparatus and configured for adjustably introducing selected signal impairments into said radio signal in order to controllably impair said radio signal as it is sent from said first radio device to said second radio device;

transmission control means for providing a transmission control input to said first radio device; and

reception monitoring means for receiving a reception monitoring output from said second radio device.

2. The radio test apparatus of claim 1, wherein said first and second chambers are constructed as waveguides.

3. The radio test apparatus of claim 1, further including radio support and positioning members mounted in said first and second chambers for supporting and positioning said first and second radio devices.

4. The radio test apparatus of claim 1, wherein said signal-carrying conductor is coupled to said first and second chambers by an antenna probe mounted in each of said chambers.

5. The radio test apparatus of claim 1, wherein said signal-carrying conductor is a coaxial cable.

6. The radio test apparatus of claim 1, wherein said transmission control means includes one or more input connectors mounted to said first chamber, said one or more input connectors being configured on one side for connection to said first radio device and on the other side for connection to a transmission control device.

7. The radio test apparatus of claim 1, wherein said reception monitoring means includes one or more output connectors mounted to said second chamber, said one or more output connectors being configured on one side for connection to said second radio device and on the other side for connection to a reception monitoring device.

8. The radio test apparatus of claim 6, further including a transmission control device connected to said one or more input connectors for controlling the transmission of said radio signal by said first radio device.

9. The radio test apparatus of claim 7, further including a reception monitoring device connected to said one or more output connectors for monitoring the reception of said radio signal by said second radio device.

10. The radio test apparatus of claim 1, wherein said signal control device includes a signal attenuator and said selected signal impairments include a signal attenuating component.

11. The radio test apparatus of claim 1, wherein said signal control device is connected to said signal-carrying conductor.

12. The radio test apparatus of claim 11, wherein said signal control device includes an output coupler for coupling signals out of said signal-carrying conductor.

13. The radio test apparatus of claim 12, further including a signal monitoring device attached to said output coupler for monitoring the effect of said selected signal impairments on said radio signal.

14. The radio test apparatus of claim 11, wherein said signal control device includes an input coupler for coupling signals into said signal-carrying conductor.

15. The radio test apparatus of claim 14, further including a signal generating device attached to said input coupler for adjustably introducing one or more interference and/or noise signals into said radio signal.

16. The radio test apparatus of claim 1, further including auxiliary means for introducing a signal input into said first chamber or receiving a signal output from said first chamber.

17. The radio test apparatus of claim 16, wherein said auxiliary means includes one or more auxiliary connectors mounted to said first chamber, said connectors being configured on one side for connection to said first radio device and/or an antenna, and on the other side for connection to signal generating or receiving equipment.

18. A controlled environment radio test method, comprising the steps of:

providing a controlled environment radio test apparatus, said radio test apparatus comprising;

a first chamber for receiving a first radio device therein;

a second chamber for receiving a second radio device therein;

said first and second chambers being sized in proportion to an operational frequency of said first and second radio devices to be tested;

a signal-carrying conductor coupled to said first and second chambers to carry a radio signal transmitted by said first radio device for reception by said second radio device;

a signal control device connected to said radio test apparatus and configured for adjustably introducing selected signal impairments into said radio signal in order to controllably impair said radio signal as it is sent from said first radio device to said second radio device;

transmission control means for providing a transmission control input to said first radio device; and

reception monitoring means for receiving a reception monitoring output from said second radio device;

the radio test method comprising the steps of;

placing said first and second radio devices in said first and second chambers;

controlling said first radio device through said transmission control means to transmit said radio signal;

activating said signal control device to introduce said selected signal impairments into said radio signal; and

monitoring said second radio device through said reception monitoring means to determine the effect of said selected signal impairments on said second radio device.

19. The radio test method of claim 18, wherein said monitoring step includes monitoring said second radio device for signal strength and for signal noise and distortion.

20. The radio test method of claim 18, wherein said radio test apparatus includes an output coupler attached to said signal carrying conductor, and said method further includes the step of monitoring said selected impairments of said radio signal through said output coupler.

21. The radio test method of claim 18, wherein said radio test apparatus includes an input coupler attached to said signal carrying conductor, and said method further includes the step of introducing one or more interference and/or noise signals into said radio signal through said input coupler.

22. The radio test method of claim 18, wherein said radio test apparatus further includes auxiliary means for introducing a signal input into said first chamber or receiving a signal output from said first chamber, and wherein said method further includes the step of introducing one or more additional signals into said radio signal through said auxiliary means.

23. The radio test method of claim 18, further including a calibrating step performed prior to placing said first and second radio devices in said first and second chambers comprising:

placing a transmitting antenna said first chamber at a location where said first radio device is to be placed;

placing a receiving antenna in said second chamber at a location where said second radio device is to be placed;

providing a calibration signal to said transmitting antenna through said transmission control means;

monitoring said calibration signal at said receiving antenna through said reception monitoring means; and

determining from said monitoring step the signal loss characteristics of said radio test apparatus.

24. The radio test method of claim 23, wherein said calibration step further includes:

removing said transmitting antenna and said receiving antenna from said first and second chambers; and

positioning said first and second radio devices in said first and second chambers so that said radio signal is maximized at said second radio prior to introducing said selected impairment into said radio signal.

25. A radio test apparatus, comprising:

a first rectangular waveguide chamber made from a radio wave-reflective material for receiving a first radio device at a first end thereof, said first radio device being adapted to transmit a radio signal at a predetermined operational frequency;

a second rectangular waveguide chamber made from a radio wave-reflective material for receiving a second radio device at a first end thereof, said second radio device being adapted to receive said radio signal at said predetermined operation frequency;

said first and second waveguide chambers being sized and configured to guide said radio signal at said predetermined operational frequency in a primary Transverse Electric mode (TE₁,0), while substantially attenuating higher order TE modes;

a first radio frequency probe mounted at a second end of said first waveguide chamber;

a second radio frequency probe mounted at a second end of said second waveguide chamber;

a coaxial cable signal-carrying conductor connecting said first and second radio frequency probes and carrying said radio signal from said first waveguide chamber to said second waveguide chamber;

a signal attenuating device connected to said coaxial cable for attenuating said radio signal as it is carried in said coaxial cable;

a connector array mounted to said first waveguide chamber for attaching transmission control equipment to said first radio device;

a connector array mounted to said second waveguide chamber for attaching reception monitoring equipment to said second radio device; and

whereby said first radio device can be controlled to transmit said radio signal to said second radio device, said attenuating device can be activated to selectively attenuate said radio signal, and said second radio device can be monitored to determine changes in its reception of said radio signal as said radio signal is selectively attenuated.

26. A controlled environment radio test apparatus, comprising:

a waveguide chamber for receiving a radio device therein;

said waveguide chamber being sized in proportion to an operational frequency of said radio device to be tested;

an antenna probe mounted adjacent one end of said waveguide chamber to receive radio signals transmitted in said waveguide chamber by said radio device positioned adjacent an opposite end of said waveguide chamber;

a signal-carrying conductor coupled to said antenna probe to carry said radio signals out of said waveguide chamber;

transmission control means for providing a transmission control input to said radio device; and

reception monitoring means connected to said signal carrying conductor to monitor the output of said radio device.

27. A controlled environment radio test apparatus, comprising:

a waveguide chamber for receiving a radio device therein;

said waveguide chamber being sized in proportion to an operational frequency of said radio device to be tested;

an antenna probe mounted adjacent to one end of said waveguide chamber to transmit radio signals into said waveguide chamber to be received by said radio device positioned adjacent to an opposite end of said waveguide chamber;

a signal-carrying conductor coupled to said antenna probe to carry said radio signals into said waveguide chamber;

a reception means for receiving demodulated signal from said radio device; and

reception monitoring means connected to said signal carrying conductor to monitor the demodulated output of said radio device.