After the introduction and summary, the state of the art is explained in Chapter 2. Various antenna forms on which the work is based are presented and compact multi-antenna sets that have already been researched and implemented are mentioned. In addition to the receiving antenna component, well-known diversity approaches and circuits are explained. In Chapter 3, general mathematical framework conditions are defined, technical basics are laid and antenna and diversity terms are explained. The modes of operation of the SDARS and GNSS satellite radio systems are explained and the problems mentioned at the beginning are described in more detail. It is shown that for both satellite radio systems under consideration, the identified system-specific problems can be reduced in their impact using compact multi-antenna sets. Furthermore, it is shown how diversity systems at the receiving location must act with regard to both SDARS and GNSS in order to achieve the greatest possible effect. While signal downtimes (so-called "mute times") can be reduced in an SDARS diversity system using established combination techniques such as equal gain combining or scan phased diversity. In a GNSS diversity system, through the Receiver-controlled algorithms disruptive reflection signal paths are suppressed by intelligent stearing. Chapter 4 summarizes all antenna concepts examined in this work. Both individual antennas and compact multi-antenna sets are explained here. The functionality of the high-performance antenna shapes that make up the multi-antenna sets is explained. The designed multi-antenna sets form the basis for use in GNSS and SDARS diversity test circuits. In particular, simple and cost-effective construction methods were examined. For mobile reception of GNSS signals on vehicles, Chapter 4.2.1 presents a dual-band antenna set with three linearly independent individual signal paths and external dimensions of 42 x 42 x 20 mm³. The realized gains of the individual antennas are from 0 to 3,5 dBi for L1 and L2 band in their respective main beam directions. In addition, a high cross-polarization discrimination (XPD) of at least 10 dB is achieved across a wide band. For the reception of SDARS, a new type of three-antenna set is presented in Chapter 4.2.3, in which the three individual sheet metal antennas can be placed under a plastic cover in such a way that they are protected against electrostatic discharge from the outside. The 52 x 52 x 15 mm³ set was optimized for high-quality reception on a small surface area of 75 x 75 mm², which is designed as a compact base and acts as a mounting plate for the set. Realized gains of 0 - 4.5 dBi are achieved for all individual antennas. In addition to the design of new antenna sets, the focus of this work was on further research into novel manufacturing technologies. In this regard, the design of antenna sets based on an MID was examined. While in Chapter 4.2.4 an antenna set for GNSS reception was created using ProtoPaint painting, Chapter 4.2.5 documents the creation of an MID structure using an ordinary industrial milling machine in order to investigate an alternative form of production for the typically used, very cost-intensive injection molding technology. Both approaches made it possible to create a largely reproducible structure. All approaches to multi-antenna sets considered can be produced cost-effectively due to their simple manufacturing process, with a view to producing large quantities for the vehicle industry. In terms of their external dimensions, they do not significantly tower over typical individual antenna systems, which does not limit the possibilities of using these sets on vehicles. In order to transition to the first practical implementations and investigations of compact diversity systems, theoretical basics and important framework conditions are explained in Chapter 5. Individual technical approaches are being developed for both GNSS and SDARS in order to achieve an improvement in reception compared to a single antenna system. Chapter 6 presents a test demonstrator for a GNSS diversity system designed to amplify, phase shift and combine up to three individual antenna signals. The test demonstrator has been designed in such a way that it can be used mobile for open-field measurements. Furthermore, a test setup is presented in which the diversity system is connected to a three-antenna set and enables data analysis and manual adjustment of the diversity circuit using externally connected GNSS receivers and a laptop. To control the diversity circuit, a microcontroller was added for which a simple control program was created. In initial field tests, the functionality of the demonstrator will be showed and GNSS diversity approaches will be examined in practice. Practical identification of reflection signals was achieved using two different technical approaches. The diversity test circuit was used to demonstrate the functionality and usability of a multi-antenna set designed in this work. In Chapter 7, an antenna set designed as part of this work is combined with a compact diversity circuit from a parallel research project to form an SDARS antenna diversity system. The test demonstrator was examined in both laboratory and field tests. A significant increase in signal availability compared to a typical single antenna system was demonstrated.     «

After the introduction and summary, the state of the art is explained in Chapter 2. Various antenna forms on which the work is based are presented and compact multi-antenna sets that have already been researched and implemented are mentioned. In addition to the receiving antenna component, well-known diversity approaches and circuits are explained. In Chapter 3, general mathematical framework conditions are defined, technical basics are laid and antenna and diversity terms are explained. The mod...     »