Antenova Magnetic Dipole Technology

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1 Antenova Magnetic Dipole Technology Many aspects of this presentation are protected by UK and International Patents and Patent Applications

2 Loop Antenna Advantages Loop antennas are attractive for mobile phone applications in part, because their excited surface current paths are in a closed form, which is different from the conventional mobile phone antennas such as the monopoles or planar inverted-f antennas (PIFAs), whose excited surface current paths are in an open form. The coupling between the loop antenna and the system ground plane of the mobile phone can be much smaller than that of the conventional mobile phone antennas. The variations in the dimensions of the system ground plane will show smaller effects on the performances of the loop antenna.

3 Antenna Description The loop antenna is formed by mounting a meandered loop onto a FR4 substrate of 40mm(W) x 10mm(L) x 3.2mm(H) size The antenna is only 1.2cc in volume. The antenna is then surface-mounted to the system circuit board of the mobile phone on top of the capacitive coupled feed printed on the system circuit board. Through the capacitive coupling the 0.5, 1.0, and 1.5 wavelength modes of the surface-mount loop antenna can be successfully excited.

4 Antenna Dimensions 40mm 10mm 3.2mm

5 Direct Feed Penta-band Loop Antennas Many aspects of this presentation are protected by UK and International Patents and Patent Applications

6 Direct Feed Penta-band Version The loop antenna is mounted on the front side of the top no-ground portion (area 40mm x 12mm) of the system circuit board of the mobile phone (a 0.8mm thick FR4 substrate of area 40x110mm used here) for practical applications. A PCB of 40x100mm is used as the system ground plane of the mobile phone. We have investigated the differences in bandwidth and efficiency between the direct fed loop and the capacitive coupled loop We found that the capacitive coupled loop antenna offers significant bandwidth advantages over its direct feed counterpart

7 Direct Feed Penta-band Version: Impedance Data 10 mtool [MHz] MARKERS: MHz MHz Direct Feed Loop.S1P 1: : : : Bandwidth easily exceeds Penta-band requirement. (UK patent Application Number )

8 Direct Feed PentaBand Version Efficiency Data Free Space Terminal Efficiency [%] Frequency [MHz] GSM850 DCS1800 UMTS2100 GSM900 PCS1900 Minimum Efficiency Average Efficiency (UK patent Application Number )

9 Direct Feed Hexa-band Loop Antennas Many aspects of this presentation are protected by UK and International Patents and Patent Applications

10 Direct Feed Hexa-band Version Parasitic Radiator on Underside of PCB The Hexa-band performance comes from the radiating parasitic that is placed on the underside of the loop antenna. No modification to the main antenna was made. (UK patent Application Number )

11 Direct Feed Hexa-band Version: Efficiency Data [db] 5 mtool [MHz] MARKERS: MHz db MHz db GSM+GPS.s1p 1: : : : Bandwidth easily exceeds penta-band requirement and also includes GPS. (UK patent Application Number )

12 Direct Feed Hexa-band Version: Efficiency Data Free Space Terminal Efficiency [%] Frequency [MHz] GSM850 GPS DCS1800 UMTS2100 GSM900 PCS1900 Minimum Efficiency Average Efficiency (UK patent Application Number )

13 Ground Plane Dependence and Performance Advantages Many aspects of this presentation are protected by UK and International Patents and Patent Applications

14 Ground Plane Influence The planar inverted F antenna (PIFA) is used in many handsets because of its small size and low profile. However, the PIFA suffers gain degradation when an operator holds the handset which is caused by variations in the current distributions on the ground plane. By being excited by the PIFA, the ground plane acts as a part of the antenna and contributes to improvement of the antenna performance, particularly when the antenna element is very small. It should be noted that the currents on the ground plane increase an antenna s system gain, but instead the gain decreases when the currents are varied by the body effect. In order to avoid the antenna performance degradation, the currents on the ground plane should be minimized. These currents can be reduced by using an antenna having a balanced structure.

15 Simulated Ground Plane Current Frequency at 2 GHz Loop Antenna PIFA Antenna From the simulated current distributions we can see the loop antenna induces a lot less current on the ground plane than that of a PIFA. Thus we can expect the performance of the antenna to be less effected by environmental changes.

16 Hand Effect on Overall Antenna Performance Efficiency Loss [db] Frequency [MHz] Antenova Loop Antenna Antenova PIFA The graph shows the loss experienced by the loop antenna and a similar performing PIFA antenna. The balanced nature of the loop antenna shows that there is a performance advantage when it comes to the hand effect

17 Ground Plane Effect on a GSM Monopole Antenna Gnd Plane Decreasing Ground plane Decreasing ground plane length effects both low band and high band. Low band resonant frequency increases with decreasing bandwidth whilst high band bandwidth increases due to the ground plane becoming more of a resonant structure at 1800 MHz

18 Ground Plane Effect on a GSM Loop Antenna Gnd Plane Decreasing Ground plane The low band resonant frequency is more stable than a monopole, with the bandwidth decreasing a lot slower as the ground plane is made shorter High band bandwidth is little effected by the change in ground plane length, hence more stable performance can be achieved

19 Detuning Effects Solid metal can Case 1: Metal Can 39x40x3.2mm^3 Case 2: Metal Can 39x60x8mm^3 Can starts 1mm from ground plane edge

20 Measured Return Loss No changes to the antenna matching circuit were made. A better antenna match can obtained improving lowband performance

21 Measured Antenna Efficiency Efficiency [%] Without Shield Can With Shield Can 8mm Frequency [MHz]

22 Very Wide Band Magnetic Dipole Antennas & Adaptive Magnetic Dipole Antennas Many aspects of this presentation are protected by UK and International Patents and Patent Applications

23 Summary We can enhance the performance and bandwidth by utilising the multimode of magnetic dipole antenna. The feed of the antenna is designed so that the multimode of the loop are excited and more bandwidth can be achieved in smaller volume. We have extended this line of research into an adaptive antenna We now have a working prototype of a 10 band antenna

24 Capacitive Feed Loop Antenna The capacitive feed shape is adjusted to provide successful excitation of the antenna modes Capacitive coupling area (Antenna Underside) Capacitive Feed Strip PCB Underside (UK patent Application Number )

25 Capacitive Feed Loop Antenna: Impedance Data [db] 5 mtool5 7 mtool [MHz] [MHz] MARKERS: MHz db MHz db 7 band.s1p 1: : : : MARKERS: MHz MHz 7 band.s1p 1: : : : MHz Bandwidth in the lowband & 1GHz Bandwidth in the highband (UK patent Application Number )

26 Capacitive Feed Octo-band Version: Efficiency Data Free Space Terminal Efficiency [%] GSM850 GSM900 DCS1800 PCS1900 UMTS2100 W IMAX 2.3 Ghz WIFI Frequency [MHz] WIMAX 2.5 Ghz Minimum Efficiency Average Efficiency (UK patent Application Number )

27 Extending Performance into LTE A Deca Band Antenna is following on from the capacitive fed loop antenna, but now incorporates adaptive frequency switching The antenna can cover the following bands 1. LTE GSM GSM DCS PCS UMTS WiMax 2.3GHz 8. Wi-Fi( GHz) 9. WiMax 2.5GHz 10. LTE 2.7 GHz (UK patent Application Number )

28 Antenna Dimensions Features Antenna Dimensions: 40mm(W) x 10(L)mm x 3.2(H)mm Antenna Volume: 1.2cc GND Plane: 100mm x 40mm Dual Capacitance Feed Active Band Tuning

29 Adaptive Antenna Switching Extends the Original Reflexus Design to incorporate dual capacitance feeding for UWB like performance in GSM Bands Also employs the use of Active Band switching to achieve LTE-700 MHz band Position 1 760MHz to 800 and GHz Position MHz to 760 MHz and GHz To ground Position MHz to 2.7+ GHz

30 Switched Mode - 1 Lowband Mode 1 Antenna Frequency Range 0.8 GHz to 2.7 GHz

31 Switched Mode Loop - 2 Lowband Mode 2 Antenna Frequency Range Lowband now changed to cover LTE Mid Band 750 to 800 Mhz. Antenna still covers Highband of 1.7 to 2.7 GHz

32 Switched Mode Loop - 3 Lowband Mode 3 Antenna Frequency Range Lowband now changed to cover LTE LOW Band 700 to 760 Mhz. Antenna still covers Highband of 1.7 to 2.7 GHz

33 Measured Efficiency Swtchable Lowband Efficiency [MHz] LTE Band 1 LTE Band 2 GSM850 & GSM Frequency [MHz] Switch Pos 2 Switch Pos 1 Switch Pos 3

34 Measured Efficiency GSM850, GSM900, DCS, PCS, UMTS, WiMax(2.3GHz), WiFi( ), WiMax(2.5GHz), LTE(2.7GHz) Efficiency [MHz] Frequency [MHz] Switch Pos 3

35 Conclusions Loop antennas can be successfully used in mobile phones and other electrically small mobile platforms Directly fed loop antennas can achieve efficient penta-band and hexaband performance Capacitively fed loop antennas can achieve even more bandwidth, reaching 9 band performance Parasitic antennas can be added to create extra resonances Adaptive methods can be used to extend performance into the 700 MHz LTE frequency bands

36 Summary Antenova s value is in providing the broadest range of high-performance antenna solutions for our customers in multiple wireless applications We are a market led product and technology company The advantages of dielectrics and complementary antennas are real and provide major advantages: performance, flexibility, size, cost and convenience. Antenova s technologies provide innovative ways of designing antennas for small devices and optimizing them with RF components to respond to market and customer demand Changes are occurring requiring new products and technologies for tomorrow s antenna requirements Antenova s Research and Development addresses these new challenges