Sat, 26 Jul 2008 06:12:45 BST CiteULike: dcastro's Nauwelaers http://www.citeulike.org/user/dcastro/author/Nauwelaers CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/dcastro/article/2762104 <i>Microwave Symposium Digest, 1994., IEEE MTT-S International (1994), pp. 1473-1476 vol.3.</i><br /><br />A novel technique is proposed for the measurements of the transducer power gain and noise figure of the amplifier embedded in a receiving active antenna, where the direct measurements with traditional techniques are impossible. The bandwidth of the active antenna can be also determined with this technique. The good agreement between the measurements and calculations of a number of active receiving microstrip antennas shows the validity of the measurement technique. This makes it possible to characterize all the performance of receiving active antennas A novel measurement technique for amplifier-type active antennas H An BKJC Nauwelaers AR Van de Capelle RG Bosisio doi:10.1109/MWSYM.1994.335133 Microwave Symposium Digest, 1994., IEEE MTT-S International (1994), pp. 1473-1476 vol.3. 2008-05-06T17:19:23-00:00 1994 Microwave Symposium Digest, 1994., IEEE MTT-S International 1473 1476 vol.3 active amplifier antenna measurement http://www.citeulike.org/user/dcastro/article/2762102 <i>Electronics Letters, Vol. 29, No. 18. (1993), pp. 1646-1647.</i><br /><br />A novel technique is presented for measuring the transducer power gain of an amplifier which is an integral part of an active microstrip antenna. The bandwidth of the realised gain of the active antenna can also be determined with this technique. The validity of the proposed technique is verified by the measurement of an active microstrip antenna Measurement technique for active microstrip antennas H An B Nauwelaers A van de Capelle doi:10.1049/el:19931096 Electronics Letters, Vol. 29, No. 18. (1993), pp. 1646-1647. 2008-05-06T17:19:03-00:00 1993 Electronics Letters 29 18 1646 1647 active antenna microstrip http://www.citeulike.org/user/dcastro/article/2762100 <i>Electronics Letters, Vol. 29, No. 18. (1993), pp. 1594-1596.</i><br /><br />A novel technique for the measurement of the noise figure is proposed for an amplifier embedded in a receiving active microstrip antenna, where direct measurement is impossible. The proposed technique is a combination of the transducer power gain measurement of the amplifier and the absolute noise power measurement of the active antenna. The measured results of a receiving active microstrip antenna show the validity of the measurement technique. This enables the characterisation of the noise performance of active antennas Noise figure measurement of receiving active microstrip antennas H An B Nauwelaers A Van de Capelle doi:10.1049/el:19931062 Electronics Letters, Vol. 29, No. 18. (1993), pp. 1594-1596. 2008-05-06T17:19:01-00:00 1993 Electronics Letters 29 18 1594 1596 active antenna measurement microstrip noise receiving http://www.citeulike.org/user/dcastro/article/2762099 <i>Antennas and Propagation, IEEE Transactions on, Vol. 42, No. 2. (1994), pp. 129-136.</i><br /><br />A new approach is proposed to increase the bandwidth of microstrip antennas by designing the impedance matching network with the simplified real frequency technique. The most significant feature of this numerical technique is that it does not require any analytical description of the antenna and generator, the measured or simulated impedance data are processed directly. Furthermore, neither an a priori choice of a matching network topology nor an analytic form of the system transfer function is needed. The matching network realized with this technique is generally simple and gives superior gain properties compared to that obtained by other methods. Two representative design examples of microstrip antennas with different bandwidth show the validity of the design procedure Broadband microstrip antenna design with the simplified real frequency technique Hongming An BKJC Nauwelaers AR van de Capelle doi:10.1109/8.277206 Antennas and Propagation, IEEE Transactions on, Vol. 42, No. 2. (1994), pp. 129-136. 2008-05-06T17:18:59-00:00 1994 Antennas and Propagation, IEEE Transactions on 42 2 129 136 antenna broadband design microstrip http://www.citeulike.org/user/dcastro/article/2762095 <i>Electronics Letters, Vol. 27, No. 25. (1991), pp. 2378-2379.</i><br /><br />The design is presented of active microstrip array elements by the combination of active devices with radiating patches to obtain broad bandwidth and extra power gain. The design is illustrated with an active microstrip transmit antenna in a two sided structure. In terms of the realised gain with a flatness of ±0.45 dB, a bandwidth of 24% of the centre frequency was achieved. The results are very attractive for broadband MIC active array design Broadband active microstrip array elements H An B Nauwelaers A Van De Capelle Electronics Letters, Vol. 27, No. 25. (1991), pp. 2378-2379. 2008-05-06T17:16:19-00:00 1991 Electronics Letters 27 25 2378 2379 active antenna array broadband microstrip http://www.citeulike.org/user/dcastro/article/2762094 <i>Antennas and Propagation, IEEE Transactions on, Vol. 42, No. 12. (1994), pp. 1612-1619.</i><br /><br />This paper deals with the design of broadband active microstrip antennas where the amplifier is integrated with the radiator. Theoretically sound definitions for gain and noise figure of the active antenna are introduced, and their relationships with the definitions for the composing circuit and radiator parts are explained. A sequential design procedure is presented that allows the straightforward and optimal design of transmitting and receiving antennas with multiple active stages, taking into account input and output matching, the gain-versus-frequency curve as well as the noise performance. The theoretical concepts are illustrated with two examples: one of a transmitting active antenna and one of a receiving antenna. The former one is a two-stage design that achieves nearly 25% of bandwidth with regard to gain and matching and 24 dB gain improvement as compared to the matched passive antenna. The second one is a receiving antenna (one stage) with a measured noise figure of 1.2 dB in a bandwidth of over 17% and a gain improvement of 11.9 dB over the corresponding passive antenna. Finally co- and cross-polar radiation patterns in E- and H-plane prove that the antennas also have favorable radiation characteristics in a wide bandwidth (at least 18%) Broadband active microstrip antenna design with the simplified real frequency technique Hongming An BKJC Nauwelaers AR Van de Capelle doi:10.1109/8.362813 Antennas and Propagation, IEEE Transactions on, Vol. 42, No. 12. (1994), pp. 1612-1619. 2008-05-06T17:16:14-00:00 1994 Antennas and Propagation, IEEE Transactions on 42 12 1612 1619 active antenna broadband design microstrip