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A concept for multiple-input, multiple-output antenna arrays, integrated in an ultra-thin full metal cover laptop computer, is proposed. The antennas are for octa-band wireless wide area network (WWAN) and triple-band wireless local area network (WLAN) operation. The proposed solution makes use of the gap between the metallic display lid and keyboard chassis to form notch and slot antenna arrays, thereby removing the need for additional protrusions or openings. Simulated as well as measured performance is presented. The notch antenna array for WWAN exhibits wide impedance bandwidth, with more than 24 dB isolation from 690 MHz to 3 GHz, and a total efficiency better than -2.5 dB. The slot antenna array for WLAN shows more than 12 dB isolation and a total efficiency of more than -3 dB. Both arrays exhibit a very low envelope correlation coefficient of less than 0.1 within their respective frequency bands.

The integration of an on-chip folded dipole antenna with a monolithic 24-GHz receiver manufactured in a 0.8-mum SiGe HBT process is presented. A high-resistivity silicon substrate (1000 Omega ldr cm) is used for the implemented circuit to improve the efficiency of the integrated antenna. Crosstalk between the antenna and spiral inductors is analyzed and isolation techniques are described. The receiver, including the receive and an optional transmit antenna, requires a chip area of 4.5 mm2 and provides 30-dB conversion gain at 24 GHz with a power consumption of 960 mW.

A compact and flexible fiber-optic cell for absorbance detection in capillary electrophoresis (CE) has been developed. Optical fibers with a large core diameter were combined with focusing optics and a circular aperture, the size of the aperture being matched to the I.D. and O.D. of the separation column, in order to maximize light throughput and reduce stray light. The detection limit for mesityl oxide was 1.5 μM for a 100-μm I.D. column, and the linear dynamic range was larger than 1000 for columns from 100-μm I.D. down to 30-μm I.D. The design is suitable for high-speed CE, utilizing short columns.

An on-ground internal antenna for FM radio reception in mobile phones is proposed and evaluated. By combining a parasitic loop radiator with a driven active monopole antenna, a dual resonant frequency response is achieved with an average effective antenna efficiency of −22.5 dB over the frequency band 88–108 MHz. The total volume of the antenna is 0.93 cm3 with a height above ground of 4 mm. A comparison with the conventional solution of re-using the headset cord as the antenna is included.

An antenna concept for FM radio reception in mobile phones is proposed and evaluated. By resonating a loop or monopole radiator with a shunt element and connecting the antenna to a high-impedance low noise amplifier, an equivalent antenna efficiency of −24±3 dB is achieved over the entire band of 88 – 108 MHz despite having high-Q gain characteristics and without using control voltages for frequency tuning. Due to the resonant frequency behavior ≫45 dB isolation against co-located transmitting antennas is realized, thereby preventing the amplifier from being saturated during simultaneous operation. A comparison with the hands-free cord and other possible internal solutions is included.

During recent years, it has become evident that mobility functions will have a profound impact on current and future wireless networks. Users expect service connectivity anywhere and anytime without having to think about the underlying communication systems used at that particular moment in time. On this background, this paper presents a ready-to-deploy implementation of a mobility framework that supports seamless communication and represents an important enabler for adaptive applications through its simple QoS feedback mechanism. The framework selects the best available network through a decision algorithm that takes advantage of both experience with different network types for certain types of services and a link performance monitoring concept. The impact of the proposed framework on performance in terms of processing and throughput overhead is also discussed.

In this paper, matched performance of a double band PIFA antenna is reported. The transducer power gain of the antenna is optimized over the commercialized wireless communication bands of 824-960 MHz and 1710-1990 MHz using only one matching network. In the design process, several commercially available computer aided design packages with variety of different matching network topologies were employed. The best result was obtained by using the Simplified Real Frequency Technique, which in turn yields an "easy to implement circuit topology". The matched antenna provides an average transducer power gain of -1.6±0.4 dB in 824-960 MHz and -2.2±0.5 dB in 1710-1990 MHz. Inst. Electronics, Information Communication Eng., IEICE Japan,IEEE MTT-S,URSI,EuMA,IEEE MTT-S Japan Chapter

Miniaturization, low cost and excellent performances at microwave and millimeterwave applications represent the main leitmotivs of the future mass market communication systems. Consequently, a novel "MEMS above IC" technology has developed in order to allow the elaboration of post-processed micro-machined passive components on top of SiGe circuits to realize a complete short-range communication receiver centered at 24 GHz. The developed technology is based on the use of : -a thick organic layer (BCB), which is employed as a dielectric membrane, -metallizations to realize the passive metal layer and also the vias to interconnect the active circuits with the post-processed passive components, -and a bulk silicon micromachining. This 'above IC' technology presents many advantages, as it uses conventional equipments of microelectronics and is in adequation with high frequency applications. A specific attention has been carried out in order to assure the compatibility of the post-process steps and the IC’s. This has been performed through the choice of the adequate technological steps, which had to present a low temperature budget. The compatibility of each step has been evaluated with a specific test protocol on SiGe transistors. It implies static and dynamic characterisation of these transistors as well as low frequency noise measurements. Each step has been validated, even the bulk silicon micromachining. Design rules have thus been defined in order to localize the silicon etching without any damage on the ICs.

The paper presents an IQ-demodulator for use in a 24 GHz direct conversion receiver. The circuit has been monolithically implemented in a commercial SiGe HBT process production line using a standard (20 /spl Omega/cm) substrate. Measured results show a conversion gain of 11 dB, a LO/RF isolation of 35 dB and a 1-dB compression point of -10 dBm while consuming 101 mA at 3 V Vcc.

The integration of an on-chip dipole antenna with a monolithic 24 GHz receiver manufactured in a 0.8 /spl mu/m SiGe HBT process is presented. A high resistivity silicon substrate (1000 /spl Omega/cm) is used for the implemented circuit to improve the efficiency of the on-chip antenna. The receiver, including the receive and an optional transmit antenna, requires a chip area of 7.3 mm and delivers 33 dB conversion gain at 24 GHz.

A printed dipole antenna with integrated balun is presented. The radiating structure is a two-element dipole with resonances at 900 and 1700 MHz, with the balun providing one extra resonance at each band. By co-designing the radiating element with a Marchand balun modified for dual-band operation, an antenna covering the cellular bands 824-960 and 1710-2170 MHz has been achieved. Measurements on a fabricated antenna on low-cost FR-4 substrate show antenna efficiencies of >80 and >70% in the lower and upper band respectively. Despite the use of a dual-element radiator, the radiation pattern that is close to omni-directional H-plane is obtained

A modified earpiece cord is proposed and evaluated as a wideband antenna for DVB-H reception. By winding the cord into a high-impedance RF choke at one-quarter wavelength distance from the handset connection, a stable wideband input impedance is achieved. Using two-chip components for impedance matching, the complete UHF band can be covered with >35% antenna efficiency. Measured and simulated results are presented with good agreement.