**4. Experimental and practical results**

On the base of simulation results, the prototype was fabricated on FR-4 and coupled with coaxial cable of 75 ohms (see Figure 10). In Figure 11, the spectrum analyzer displays the two ranges frequencies received with the prototype: (58.75 MHz, 109.37 MHz) and (155.5MHz, 238.75 MHz), the maximum peak response has a value of -38.5 dBm. Even the primary results shown here, more experimental analysis must be still realized, but it must be recognized that our laboratory equipment is limited.

Fig. 10. (a) Patch antenna array prototype. (b) Prototype mounted on a PVC base, outdoors of the CIICAp building.

The received range frequencies for the case of a rabbit-ear antenna are shown in Figure 12, where it can be also noted two frequency ranges: (88 Mhz, 108.25 MHz) and (171.25MHz, 182.5 MHz), with a maximum peak of -50 dBm. From these photographs, the bigger

Low Cost Prototype of an Outdoor Dual Patch Antenna

Array for the Openly TV Frequency Ranges in Mexico 235

Reception with the prototype

Channel 5 Channel 9

Channel 7 Channel 13 Reception with the commercial combined indoor antenna

Channel 5 Channel 9

Channel 7 Channel 13

receptions of the patch antenna array are clearly noted, as well as the received power. Even the primary results shown here, more experimental analysis must be still realized.

Fig. 11. Two received range frequencies with the spectrum analyzer with the prototype of the antenna array.

Fig. 12. Two received range frequencies with the spectrum analyzer with a rabbit-ear antenna.

On the other hand, practical tests were also realized on different places of Morelos State. The first ones were realized outside of CIICAp building (18°58'56'' N, 99°14'1.9'' WO), with the antenna located approximately at only 2 meters of the ground. The photographs are shown in Table 7.

Using an analogical TV, a comparison of the reception of the most common channels, considering two commercial antennas (a mini-combined antenna (Figure 13) and a rabbitear antenna) and the prototype was also realized.

receptions of the patch antenna array are clearly noted, as well as the received power. Even

Fig. 11. Two received range frequencies with the spectrum analyzer with the prototype of

Fig. 12. Two received range frequencies with the spectrum analyzer with a rabbit-ear

On the other hand, practical tests were also realized on different places of Morelos State. The first ones were realized outside of CIICAp building (18°58'56'' N, 99°14'1.9'' WO), with the antenna located approximately at only 2 meters of the ground. The photographs are shown

Using an analogical TV, a comparison of the reception of the most common channels, considering two commercial antennas (a mini-combined antenna (Figure 13) and a rabbit-

the antenna array.

antenna.

in Table 7.

ear antenna) and the prototype was also realized.

the primary results shown here, more experimental analysis must be still realized.

Low Cost Prototype of an Outdoor Dual Patch Antenna

also received (11 and 13; see table 8).

Array for the Openly TV Frequency Ranges in Mexico 237

On the other side, the antenna prototype was also used on a house roof, in three different places using digital TVs. At first, the tests were realized for a household reception in Temixco, Morelos (located at 18. 51° N, 99º13'48'' WO, with a height over sea level: 1,280 m). In Table 8, photographs of four analogycal representative channels are shown, with a considerable sharpness in all them. In this place, two High Definition (HD) channels were

Reception with the prototype

Channel 2 Channel 5

Channel 7 Channel 13

Channel 11 HD Channel 13 HD

As second case, other tests were realized considering our prototype and a rabbit-ear antenna for a household reception in Monte Casino (located at 19°00'53.7'' N, 99°14'50.6'' WO, height over sea level: 2250 m). With the prototype the reception of the analogical channels was possible without problems, with better sharpness that in the case of the rabbit-ear antenna.

Table 8. TV channels reception using a LCD TV.

Table 7. TV channels reception of openly TV using a scanning TV.

Fig. 13. Mini-combined antenna.

As it can be observed from Table 7, the best reception was achieved with the patch antenna array, followed by the reception with the combined antenna, where some problems were appreciated in channels 5 and 13. The antenna with more reception problems was the rabbitear antenna.

Reception with the Rabbit-ear antenna

Channel 5 Channel 9

Channel 7 Channel 13

As it can be observed from Table 7, the best reception was achieved with the patch antenna array, followed by the reception with the combined antenna, where some problems were appreciated in channels 5 and 13. The antenna with more reception problems was the rabbit-

Table 7. TV channels reception of openly TV using a scanning TV.

Fig. 13. Mini-combined antenna.

ear antenna.

On the other side, the antenna prototype was also used on a house roof, in three different places using digital TVs. At first, the tests were realized for a household reception in Temixco, Morelos (located at 18. 51° N, 99º13'48'' WO, with a height over sea level: 1,280 m). In Table 8, photographs of four analogycal representative channels are shown, with a considerable sharpness in all them. In this place, two High Definition (HD) channels were also received (11 and 13; see table 8).

Table 8. TV channels reception using a LCD TV.

As second case, other tests were realized considering our prototype and a rabbit-ear antenna for a household reception in Monte Casino (located at 19°00'53.7'' N, 99°14'50.6'' WO, height over sea level: 2250 m). With the prototype the reception of the analogical channels was possible without problems, with better sharpness that in the case of the rabbit-ear antenna.

Low Cost Prototype of an Outdoor Dual Patch Antenna

Array for the Openly TV Frequency Ranges in Mexico 239

Reception with the prototype

Channel 4 Channel 8

Channel 39 Channel 45

Channel 10 Channel 21 (Repetition of channel 10)

Fig. 15. Location of the antennas used on a house roof in Morelia, Mich.

Special attention was focused on signal level of the HD reception of the single channel received there, due to this attribute of the TV. In Tables 9 and 10 the signal intensities are shown for both cases.


Table 9. HD reception with a rabbit-ear antenna.


Table 10. HD reception with the patch antenna prototype.

When the prototype was used as outdoor antenna, the maximum intensity reception was obtained (see Table 11 and Figure 14).


Table 11. HD reception with the patch antenna prototype located on the house's roof.


Fig. 14. Visualized images of HDTV reception antenna using the patch prototype, which is located on the house's roof.

Finally, the third place where the tests were realized was Morelia, Michoacan (19º43' N, 101º12' WO), another Mexican State. The tests were realized using a LCD TV with our prototype and a commercial aerial antenna (Figure 15). The results are shown in Table 12.

From Table 12, it can be observed that the TV reception is better in the case of the prototype not only for the analogical channels, receiving an additional one, but also for the single HD channel received (1.1). It must be noted that the location of both antennas is not the best (Figure 15), but several homes in our country have similar conditions. The sizes of the antenna array prototype are considerable smaller than the available aerial antenna.

Special attention was focused on signal level of the HD reception of the single channel received there, due to this attribute of the TV. In Tables 9 and 10 the signal intensities are

TV channel Current level (%) Maximum level (%)

TV channel Current level (%) Maximum level (%)

When the prototype was used as outdoor antenna, the maximum intensity reception was

TV channel Current level (%) Maximum level (%)

Fig. 14. Visualized images of HDTV reception antenna using the patch prototype, which is

Finally, the third place where the tests were realized was Morelia, Michoacan (19º43' N, 101º12' WO), another Mexican State. The tests were realized using a LCD TV with our prototype and a commercial aerial antenna (Figure 15). The results are shown in Table 12.

From Table 12, it can be observed that the TV reception is better in the case of the prototype not only for the analogical channels, receiving an additional one, but also for the single HD channel received (1.1). It must be noted that the location of both antennas is not the best (Figure 15), but several homes in our country have similar conditions. The sizes of the

antenna array prototype are considerable smaller than the available aerial antenna.

Table 11. HD reception with the patch antenna prototype located on the house's roof.

13.1 44 48

13.1 50 55

13.1 59 59

Table 9. HD reception with a rabbit-ear antenna.

obtained (see Table 11 and Figure 14).

located on the house's roof.

Table 10. HD reception with the patch antenna prototype.

shown for both cases.

Fig. 15. Location of the antennas used on a house roof in Morelia, Mich.

Low Cost Prototype of an Outdoor Dual Patch Antenna

Not available

**5. Conclusions** 

sub-ranges of frequencies.

where they were available.

prototype to the weather.

**6. Acknowledgment** 

material, but its costs will be incremented.

suggest its use as outdoor antenna.

Array for the Openly TV Frequency Ranges in Mexico 241

Channel 13 (HD) Channel 1.1

The simulations of the patch antenna array show its dual frequency performance. In spite of the inherent narrow broadband of the microstrip antennas, the practical reception, realized in different geographical sites of Morelos and in Morelia, Michoacan, has also confirmed the

The difference in the TV reception can be attributed to the proximity of the repeaters

The experimental and practical tests show an acceptable reception of channels in both VHF

In TVs that accounts with graphical signal meter, it was possible to observe that with the antenna on the house's roof, the current signal meter obtained its maximal level, for the case of HD channels, which is certainly a very good practical result, and it constitutes a base to

In the three tests realized using digital TVs on different places, it must be mentioned that unfortunately the available TVs have different attributes, but in all cases the better reception was obtained with our prototype. The comparison with aerial antennas was only possible

The prototype sizes make it a competitive option compared with some commercial aerial antennas available in the market. Additionally, for the case of digital TVs, it does not require of an amplifier or a rotor, once it was properly directed. For the case of analogical TVs the

As future work, it is planned to design an appropriate radome for protection of the

The implementation of geometry modifications is also been considered in order to increment the broadband of the antenna array. Its sizes can be also reduced using another

The authors wish to thank to EM Software & Systems (USA) Inc., for FEKO license. J. G. Vera-Dimas and J. A. Damián Morales acknowledge financial support from CONACYT

reception improvement is considerable compared with the options shown here.

Table 12. Visualized images of TV received with antennas located on the house's roof.

feasibility of its use for household reception of openly TV frequency ranges.

antennas, and to the elevation conditions. The vegetation is also relevant.

Reception with the commercial aerial antenna

Table 12. Visualized images of TV received with antennas located on the house's roof.
