In the first part of this thesis a basic theory of retrodirective antenna arrays and their particular parts – antennas and mixers is summarized. Further, there is a basic summary of possibilities for an usage of retrodirective antenna arrays for an information transmission. The second part deals with the concrete retrodirective antenna array design. The design starts with creation of an antenna array model for MATLAB software. Then a suitable structure for further design is chosen. Further, particular parts of retrodirctive antenna array – a patch antenna, a mixer, a low-pass filter, a bandstop filter, a signal combiner and a Wilkinson power divider are designed and analyzed in Ansoft Designer software. For the patch antenna analysis also CST Microwave Studio software is used. The following part deals with the realization of particular parts of the retrodirecive antenna array and its parameters measuring.

This thesis describes the basic principles of radio frequency identification, basic characteristics of patch antennas, the possibility of their feeding and design of planar antenna series. Are discussed, impedance matching options. The selected antenna arrays were realised, measuring their parameters was down and measured parameters was compared with simulation results.

The aim of this thesis is to design and rectena that would be able to integrate into a cloth thanks to use of textile substrate. The first part deals with the possibilities of using various communication channels and services for maximizing the useable power. Attention is focused mainly on the use of textile materials for implementing microstrip circuits. It is made valorization of all the typical characteristics and problems using different fabrics as a microwave substrate and the possibilities of realization of conductive structures of microwave patch antenna and microstrip circuits. At the second part are identified parameters and constraints used for the design of the overall device with a rectifying antenna, which will be after the verification of the function in real implementation used for the final concept using textile structures. The design is verified by simulations by CST Microwave Studio and Microwave Designer. The initial design is being gradually extended by other concepts, the use of other materials and technologies. Several design are made, their properties evaluated and the best ones are then compared based on real measurements.

No description available.

The Bluetooth direction finding working group proposed functionalities to the Bluetooth core that can realize Angle of Arrival estimations using interferometry. The technology can be employed to develop new access control applications. Following previous findings in Englund (2018), the purpose of this project is to investigate the feasibility of such systems when antennas are being used. The goal is to design a matchbox size antenna array which can be used by the system to distinguish between two sides in an inside-outside scenario. A number of antennas were designed, simulated and tested on a prototype. While the simulations results were consistent with the theory, the prototype measurements were not. However, it is shown that it is possible to estimate between inside and outside. / Bluetooth direction finding working group har lagt fram ett förslag om att lägga till Angle of Arrival estimerings funktionalitet baserat på en interferometri metod i Bluetooth kärnan. Tekniken kan användas för att utveckla nya åtkomstkontrolls lösningar. Detta projekt en påbyggnad av arbetet utfört av Englund (2018), syftet är att utvärdera möjligheten av en sådan åtkomstkontrolls lösning där antenner används. Målet är att designa en tändsticksask stor antenn array som kan användas av ett systemet för att särskilja mellan två sidor i ett insida-utsida scenario. Ett antal antenner konstruerades, simulerades och prototyper byggdes samt testades. Medan simuleringsresultaten var förenliga med teorin, så påvisade prototyperna inte samma beteende då resultatet skiljde sig från teorin. Projektet konstaterar dock att det är möjligt att skilja mellan insida och utsida.

Yes / Recent studies and research have centred on new solutions in different elements and stages to the increasing energy and data rate demands for the fifth generation and beyond (B5G). Based on a new-efficient digital beamforming approach for 5G wireless communication networks, this work offers a compact-size circular patch antenna operating at 60 GHz and covering a 4 GHz spectrum bandwidth. Massive Multiple Input Multiple Output (M–MIMO) and beamforming technology build and simulate an active multiple beams antenna system. Thirty-two linear and sixty-four planar antenna array configurations are modelled and constructed to work as base stations for 5G mobile communication networks. Furthermore, a new beamforming approach called Projection Noise Correlation Matrix (PNCM) is presented to compute and optimise the fed weights of the array elements. The key idea of the PNCM method is to sample a portion of the measured noise correlation matrix uniformly in order to provide the best representation of the entire measured matrix. The sampled data will then be utilised to build a projected matrix using the pseudoinverse approach in order to determine the best fit solution for a system and prevent any potential singularities caused by the matrix inversion process. The PNCM is a low-complexity method since it avoids eigenvalue decomposition and computing the entire matrix inversion procedure and does not require including signal and interference correlation matrices in the weight optimisation process. The suggested approach is compared to three standard beamforming methods based on an intensive Monte Carlo simulation to demonstrate its advantage. The experiment results reveal that the proposed method delivers the best Signal to Interference Ratio (SIR) augmentation among the compared beamformers

Due to the increasing demand and a more complicated environment for signal transmitting, the traditional antenna can hardly satisfy the current technology needs. For a telecommunication service provider, a dual-band integrated antenna array is a good way to reduce cost and increase the capacity since it can operate at different bands. The active part can also achieve beam-forming to adapt to multiple environments. Since two arrays are integrated together, the interface and coupling will be a problem. The performance of the active array is also important since it is supposed to be operated at a complex environment. This thesis will focus on how to achieve better performance of active array and reduce the impact of passive array such as mutual coupling and the change of field distribution of active array. In this thesis project, the limiting factor for the performance of active array is the narrow bandwidth. To solve that, we use another layer of parasitic patch to generate multiple resonances near the fundamental mode. For the passive antenna array, we use crossed-dipole such that the thin wires will block less signal. The return loss result and radiation pattern comparison can show that the bandwidth is broadened with parasitic patches, and the passive array has little influence on the active array. It is a proper way to design a dual-band antenna product with a low budget. / På grund av den ökande efterfrågan och en mer komplicerad miljö för signalsändning kan den traditionella antennen knappast tillfredsställa den nya teknologins behov. För leverantören av telekommunikationstjänster är en integrerad dubbelbandsantennuppsättning ett bra sätt att minska kostnaderna och öka kapaciteten eftersom den kan fungera på olika band. Den aktiva delen kan också uppnå strålformning för att anpassa sig till flera miljöer. Eftersom två arrayer är integrerade tillsammans blir gränssnittet och kopplingen ett problem. Prestandan för en aktiv array är också viktig eftersom den är tänkt att användas i en komplex miljö. Detta examensarbete kommer att fokusera på hur man uppnår bättre prestanda för en aktiv array och minskar effekten av den passiva arrayen. För det här examensarbetet är den främsta faktorn som begränsar prestandan för aktiv array den smala bandbredden. För att lösa detta använder vi ett annat lager av parasitisk patch för att generera flera resonanser nära det grundläggande läget. För passiv antennuppsättning använder vi korsade dipoler så att de tunna ledningarna blockerar mindre av signalen. Jämförelsen av returförlustresultatet och strålningsmönster kan visa att bandbredden breddas med parasitiska patch, och den passiva arrayen har liten inverkan på den aktiva arrayen. Det är ett riktigt sätt att designa en dual-band antennprodukt med en låg budget.

Yes / A compact design of multi-sector patch antenna array for 60 GHz applications is presented and discussed in details. The proposed design combines five 1×8 linear patch antenna arrays, referred to as sectors, in a multi-sector configuration. The coaxial-fed radiation elements of the multi-sector array are designed on 0.2 mm Rogers RT5880 dielectrics. The array operates in the frequency range of 58-62 GHz and provides switchable directional/omnidirectional radiation beams with high gain and high directivity characteristics. The designed multi-sector array exhibits good performances and could be used in the fifth generation (5G) cellular networks. / European Union’s Horizon 2020 research and innovation programme under grant agreement H2020-MSCA-ITN-2016 SECRET-722424

As multimedia devices advance, current high-speed wireless standards may soon struggleto support their growing demand for data speeds. This results in limitations in bandwidthfor applications, notably affecting activities like streaming high-definition television andultra-high-definition video. The proposed solution is to go up in frequency (millimeterwaves) allowing for use of greater bandwidths, in new bands. A problem is, however,that the path loss at mmWave frequencies is substantially greater than at frequencies below6GHz, currently the main frequency range used by both cellular and Wi-Fi. In order tocompensate for the increase in pathloss, wireless systems operating at mmWave frequenciesneed to use high gain antennas e.g. antenna arrays. Such arrays operate using digital oranalog beamforming. In this thesis the design, fabrication and verification of an analogbeamforming network connected to a four-antenna element patch array implemented at26GHz on a four-layer printed circuit board is presented. The components of the structuresof the Butler matrix beamforming network were designed and evaluated in simulationsusing CST. The stack up is a four-layer PCB-board with antenna elements and feedingnetwork on opposite outer layers. All structures in the Butler matrix were constructedin micro strip line with characteristic impedance of 50 ohm on Rogers RT-duroid 5880substrate to reduce dielectric losses. The designed 4x4 Butler matrix aimed at four set stateswith progressive phase differences ±45 and ±135 resulting in main lobes with direction -40,-15, 14 and 39 degrees. In the simulation, a progressive phase difference up to a deviationof up to 8.6 degrees was observed for all states. The fabricated Butler matrix was verified onan antenna measurement range to have main lobe directions of -45, -15, 15 and 40 degreesand with half power beam widths (HPBW) of 27.5, 25, 25 and 27.5 degrees respectively.The nulls between each lobe in the radiation pattern had a relative gain compared to peakvalue of -12.2 dBi resulting in similar magnitude as noise floor. The side lobe suppressionwere evaluated to minimum of 6.3 dB. The high directivity and well-defined nulls confirmthe hybrid couplers properties of equal power division as well as phase difference betweenoutput ports. The patch antennas were verified to have a dominant linear polarization butthe peak value for all lobes shows a deviation of -4.1 dB for all measurements comparedto simulation. In conclusion the final patch antenna array and Butler matrix performed asexpected from the simulation. Indicating that the proposed analog beam forming antennadesign is robust and well suited to be used in e.g. Open RAN applications.

The use of phased array antennas in present day technology is limited, primarily due to the extremely high cost of implementation. This cost is contributed to the expense of phase shifters, which are the traditional method of beam steering in phased arrays. The need to alleviate this cost and avail the technology for commercial use necessitates study into alternative mechanisms for accomplishing beam steering. To this effect, this research is an exploration of one such mechanism. To characterize mutual coupling between microstrip patch antennas and explore its practicality as a feed mechanism, it is necessary to understand the factors controlling the phenomenon. A parametric study of the spacing between patch antennas and the consequent coupling is presented, the results of which are discussed in detail. further study into bandwidth extension and steer controlling techniques are also shown, with discussion on the practicality and future of the mechanism as a candidate for widespread application.