A novel internal antenna has been developed for indoor reception of UHF terrestrial digital TV broadcasting. The overall size of some configurations of the new antenna is less than 2？cm3, and its weight is less than 1？gm. It is made of a flexible material that can be bent or folded and shaped in any form. It is an unbalanced resonant antenna that does not need a matching circuit. The new antenna can be fully embedded inside TV sets or portable computers. It has a bandwidth of about 68%. Thus, it can also cover the bands of GSM and CDMA, which is advantageous in case of portable computers. The new antenna is linearly polarized. It can be easily modified to be dual polarized by combining two orthogonal antennas with one or two feed points. The overall efficiency of some configurations of the new indoor digital TV receiving antenna is more than 80%, and its peak gain is about 2？dBi over the whole UHF band. The peak gain can be increased to more than 5？dBi by adding EBG (electromagnetic bandgap) structures. The EBG structure also increases the efficiency to around 90%. 1. Introduction The start of terrestrial digital TV broadcasting may considerably reduce the need for on-roof directional receiving antennas and increase the use of indoor antennas. Most terrestrial digital TV broadcasting channels are in the UHF band. Of course, analogue TV indoor receiving antennas can still be used with digital TV indoor reception. The most common UHF indoor digital TV receiving antennas are loop antennas and triangular dipoles [1]. However, they have large sizes and they are not rigid on top of TV sets. Also, they are balanced antennas and, hence, they need baluns. Furthermore, they are sensitive to only one polarization and, therefore, they have a poor indoor performance. Moreover, they are pure electric field antennas and, hence, their performance is significantly deteriorated in vicinity of conductive objects such as concrete walls. In addition, conventional indoor TV receiving antennas cannot be used in multi-input (MI) configurations and techniques for space and/or polarization diversity. In order to overcome some of the above problems, other indoor TV receiving antennas have been developed and published as in [2–4]. However, they are also external antennas that have to be mounted outside TV sets and they are still large in size. On the other hand, introduction of digital TV, built into portable computers, is expected in the near future. Since portable computers are getting smaller and smaller in size, they add volume limitations on digital TV antennas. Hence, it is
References
[1]
R. C. Johnson and H. Jasik, Antenna Engineering Handbook, McGraw-Hill Book Company, New York, NY, USA, 1984.
[2]
S. Kashihara and F. Kuroki, “J-shaped monopole antenna array as an antenna for terrestrial digital broadcasting at UHF band,” in Proceedings of the IEEE MTT-S International Microwave Symposium (IMS '09), pp. 293–296, Boston, Mass, USA, June 2009.
[3]
F. Kuroki and H. Ohta, “L-shaped monopole array for terrestrial broadcasting reception in the UHF band,” in Proceedings of the 37th European Microwave Conference (EUMC '07), pp. 1070–1073, Munich, Germany, October 2007.
[4]
F. Kuroki, H. Ohta, M. Yamaguchi, and E. Suematsu, “Wall-hanging type of self-complementary spiral patch antenna for indoor reception of digital terrestrial broadcasting,” in Proceedings of the IEEE MTT-S International Microwave Symposium Digest, pp. 194–197, San Francisco, Calif, USA, June 2006.
[5]
J. Kim, G. Kim, W. Seong, and J. Choi, “A tunable internal antenna with an epsilon negative zeroth order resonator for DVB-H service,” IEEE Transactions on Antennas and Propagation, vol. 57, no. 12, pp. 4014–4017, 2009.
[6]
L. Huang and P. Russer, “Tunable antenna design procedure and harmonics suppression methods of the tunable DVB-H antenna for mobile applications,” in Proceedings of the 37th European Microwave Conference (EUMC '07), pp. 1062–1065, Munich, Germany, October 2007.
[7]
L. Huang and P. Russer, “Electrically tunable antenna design procedure for mobile applications,” IEEE Transactions on Microwave Theory and Techniques, vol. 56, no. 12, pp. 2789–2797, 2008.
[8]
C. M. Chiang, A. Yang, and C. C. Chien, “Active Digital TV Antenna,” US Patent No. 0066116, 2008.
[9]
J. Liang and H. Y. D. Yang, “Radiation characteristics of a microstrip patch over an electromagnetic bandgap surface,” IEEE Transactions on Antennas and Propagation, vol. 55, no. 6, pp. 1691–1697, 2007.
[10]
F. Yang, X. X. Zhang, X. Ye, and Y. Rahmat-Samii, “Wide-band E-shaped patch antennas for wireless communications,” IEEE Transactions on Antennas and Propagation, vol. 49, no. 7, pp. 1094–1100, 2001.
[11]
M. Sanad, F. Yang, Y. Rahmat-Samii, and X. X. Zhang, “Comments on wide-band E-shaped patch antennas for wireless communications,” IEEE Transactions on Antennas and Propagation, vol. 51, no. 9, pp. 2541–2542, 2003.
[12]
M. Sanad and N. Hassan, “A resonant handset antenna that can cover all bands of UHF mobile TV, GSM and CDMA without using matching circuits,” in Proceedings of the IEEE International Symposium on Antennas and Propagation (APSURSI '10), pp. 1–4, July 2010.
[13]
M. Sanad and N. Hassan, “An internal EBG antenna for indoor reception of UHF terrestrial digital TV broadcasting,” in Proceedings of the 10th Mediterranean Microwave Symposium (MMS '10), pp. 178–181, August 2010.
[14]
M. Sanad and N. Hassan, “A 470 to 960 MHz resonant antenna: covering uhf mobile TV and CDMA/GSM without tuning circuits,” Microwave Journal, vol. 53, no. 11, pp. 56–72, 2010.
[15]
M. Sanad and N. Hassan, “A novel dual resonant antenna configuration for mobile laptop, notebook and palmtop computers,” in Proceedings of the IEEE International Symposium on Antennas and Propagation, pp. 1–4, Toront, canada, July 2010.
