The 5 GHz Wireless LAN (802.11a) is a popular standard for wireless indoor communications providing moderate range and speed. Combined with the emerging ultra Wideband standard (UWB) for short range and high speed communications, the two standards promise to fulfil all areas of wireless application needs. However, due to the overlapping of the two spectrums, the stronger 802.11a signals tend to interfere causing degradation to the UWB receiver. This presents one of the main technical challenges preventing the wide acceptance of UWB. The research work presented in this thesis is to propose a low cost RF receiver front-end filter topology that would resolve the narrowband (NB) interference to UWB receiver while being operable in both 802.11a mode and UWB mode. The goal of the dual mode filter design is to reduce cost and complexity by developing a fully integrated front-end filter. The filter design utilizes high Q passive devices and Q-enhancement technique to provide front-end channel-selection in NB mode and NB interference rejection in UWB mode. In the 802.11a NB mode, the filter has a tunable gain of 4 dB to 25 dB, NF of 8 dB and an IIP3 between -47 dBm and -18 dBm. The input impedance is matched at -16 dB. The frequency of operation can be tuned from 5.15 GHz to 5.35 GHz. In the UWB mode, the filter has a gain of 0 dB to 8 dB across 3.1 GHz to 9 GHz. The filter can reject the NB interference between 5.15 GHz to 5.35 GHz at up to 60 dB. The Q of the filter is tunable up to a 250 while consuming a maximum of 23.4 mW of power. The fully integrated dual mode filter occupies a die area of 1.1 mm2.

Att konstruera ett tidtagningssystem för enduro i skogen leder till flera frågor som måste undersökas och besvaras. Vilken kommunikationsteknik ska användas och vilken systemarkitekturisk lösning passar bäst? Att dra kabel ute i skogen är ett bra sätt att lösa det kommunikationstekniska problemet, lösningen är säker och relativt billig. Visst påverkas priset av distansen mellan olika klienter ute i skogen, men alla positiva egenskaper hos tekniken gör denna kostnad värd sitt pris. De geografiska variationer som kan finnas är de som kan spela ut de övriga teknikerna i form av stabilitet. En snabb resultatförmedling kräver ett system som har en väl uppbyggd systemarkitektur. Vid tidtagning kommer data i form av tider skickas från klienterna direkt till huvudservern, ingen mellanlagring sker utan data lagras centralt vilket förespråkas i IRM. Dessutom kommer ingen redundans att accepteras, vilket även det förespråkas av IRM. Det finns även flera andra parametrar som väger för att välja IRM, vilket är det som rekommenderas utifrån den analys som gjorts i denna uppsats.

This Thesis presents the design and development of a reconfigurable both in frequency and radiation pattern Annular Slot Antenna (ASA). The antenna is fabricated on Duroid with dielectric constant 6.15. The ASA operates in three different frequencies: 5.2, 5.8 and 6.4 GHz. The matching at those frequencies is achieved using linear stubs. PIN diodes are used as switches to connect/disconnect the stubs to the microstip feed line. The use of PIN diodes along the slot allows the steering of the radiation pattern and therefore the position of a radiation pattern null is directed in three pre-selected directions.

It is a future trend to include the function of wireless networking in portable electronic devices, such as notebooks, tablet PC, PDA, mobile phone, and other information applicants. IEEE 802.11 is the most popular wireless LAN protocol that defines the functions in the medium access control (MAC) layer and physical layer. In this thesis, we design and implement a flexible and reusable soft IP (Intellectual Property) for wireless MAC that is compatible with AMBA system and can be used in SOC applications. The wireless MAC supports buffer descriptors, interrupt and DMA. The IP provides an AMBA-compatible interface for the host system bus, and provides a communication interface for the baseband processor in the physical layer.

This thesis proposes a variety of antenna designs suitable for modern of mobile products, such as mobile phones, PDAs and so forth, on both the 2G and 3G communication systems according to the mobile communication development. Based on the integration of monopole or planar inverted-F antenna with the system ground planes, multi-frequency, broadband, and high radiation efficiency can be achieved, which is very promising to be adapted into communication products. Furthermore, an antenna capable of WLAN and UWB is proposed for future wireless communication applications.

Novel and low-cost antennas suitable for WLAN access points are presented. The operating bandwidths of the proposed antennas can cover the 2.4/5.2/5.8 GHz WLAN bands, and the antenna gain is larger than 2 and 4 dBi in the 2.4 and 5 GHz bands; respectively. Besides, they can also generate the good omnidirectional radiation patterns in the azimuthal plane. Dipole antenna, folded dipole antenna, monopole antenna and circularly polarized antenna has been applied in the proposed designs, and good antenna performance has been obtained.

It is more and more popular to transmit and receive information with Wireless LAN(WLAN) as the time of science and technology has been approaching. Every type of business gradually has priority on WLAN for marketing. Especially business of agents of real estate, they use WLAN as tool for marketing to improve the service with information and human nature and to break through the shape of traditional human operation. They record characters and functions of surrounding environment of the houses which are entrusted by clients in their system to provide immediate and local information with house-buyer. This becomes personalizing and valuable selling information. It takes both quantitative and qualitative methods as research methods in the study, and agents of real estate using and not using WLAN in Kaohsiung City are picked as research objects. The study takes depth interviews to realize conditions for wireless network marketing using, motivation for wireless network marketing, and using mode for wireless network marketing, and it also analyzes the differences among wireless network marketing, traditional marketing, and internet marketing. Meanwhile the study use questionnaires survey to figure out the reason why some agents of real estate do not use WLAN for marketing. There are four findings in the study as follows: (1) Agents of real estate using WLAN for marketing are mainly direct branches and over 15 years old. (2) The traditional way for marketing used by agents of real estate using or not using WLAN for marketing is newspaper. (3) Agents of real estate using WLAN for marketing know the requirements of clients and can improve the quality of service better then agents of real estate not using WLAN for marketing. (4) The rate of agents of real estate not using WLAN for marketing at present would like to use WLAN for marketing in the future become more. The conclusion of the study indicates the marketing mode of using new science technology can inquire new information anytime and anywhere. The mode of marketing with WLAN provides business of agents of real estate with the immediate and local information, and this is the point that mass media can not achieve. There are difficulties for business of agents of real estate in Kaohsiung City to use high science technology as a kind of marketing mode. Kaohsiung City should try to upgrade M capacity step by step and take both traditional marketing and WLAN marketing to enhance the function of WLAN for marketing in business of agents of real estate.

In the high-speed indoor wireless applications, IEEE 802.11 series is the most dominating LAN standard in the current markets. In this thesis, the design issues of the IEEE 802.11a physical layer baseband system are addressed. Various key modules including Viterbi codec, FFT/IFFT module, OFDM synchronous circuit have been integrated with several other modules to constitute the entire baseband system. This system has been implemented by Verilog HDL and verified against with the C-based behavior model. In addition, it will also be prototyped and optimized on the Altera DSP FPGA Development Board. The transmission of the I, Q channel for the time domain singal is emulated by using the 10-bits AD/DA modules on the FPGA board. The experimental results shows that the gate counts of the transmitter and the receiver are 81,190 and 413,461 respectively.

Studies of the optimum isolation in a multi-mode PDA phone are presented in this thesis. Firstly, we analyze the optimum isolation between the DCS and GPS antennas embedded in a dual-mode PDA phone. Then, we change the antenna types of the DCS system to study again the behavior of the optimum isolation. Secondly, we analyze the optimum isolation between a DCS antenna and a WLAN antenna embedded in a dual-mode PDA phone. Finally, we propose a multi-mode PDA phone for DCS, GPS, and WLAN operations with good isolation among the three internal antennas.

As the development of wireless networks, no doubt it brings much more convenience to us. Besides, QoS (Quality of Service) demand emerges due to the popularity of multimedia traffic. Therefore, it is quite worthwhile to do researches about how to provide QoS in wireless networks. 802.11 wireless networks are the most widespread wireless networks currently, and the main goal of 802.11e task group is to support QoS. This thesis proposes a method for further improving QoS under 802.11e environment. According to varying ratio of CBR-like / VBR-like traffic, it adaptively adjusts the proportion of CP/CF medium access mode, and selects the corresponding admission control mechanism. The basic philosophy is to choose favorable transfer ways for different traffic characteristics, hence to reduce average delay. In addition to reduce average delay, we propose another mechanism to maintain or improve system throughput as well.