Abstract: The present invention has for its object to provide, in an environment where plural radio systems coexist, a feed forward amplifier capable of adaptively selecting a frequency band. The feed forward amplifier of the present invention comprises a distortion detection circuit and a distortion elimination circuit and has n first vector adjusters 4 which have different operating frequency bands and are inserted in a first vector adjustment path 14 of the distortion detection circuit; and n second vector adjusters 11 which have frequency bands corresponding to those of first vector adjusters 4 and are inserted in a second vector adjustment path 8 of the distortion elimination circuit. By means of a first switching means 3 selecting one first vector adjuster 4 and a second switching means 10 selecting a second vector adjuster 11, the frequency band for which distortion component is compensated in the feed forward amplifier is controlled by switching.

Abstract: A method and apparatus for imaging a body by exposing the body to radiation transmitted through the body via successive angular portions from a radiation source on one side of the body to a radiation detector in alignment with the radiation source on the opposite side of the body; the radiation detector including a two-dimensional matrix of detector elements producing electrical outputs corresponding to the magnitudes of the radiation received by each detector element; the radiation source producing a conical beam sufficiently large such that each exposure covers all the detector elements in the two-dimensional array after traversing the body.