Showing papers on "GSM frequency bands published in 1996"

On antenna- and frequency diversity in GSM related systems (GSM-900, DCS-1800, and PCS1900)

Abstract: This paper analyze the performance of two branch antenna diversity in GSM related systems. Several combining techniques for both up- and downlink are analyzed. Frequency diversity obtained from slow frequency hopping in GSM is also considered. Finally antenna diversity results for a non-ideal antenna configuration, i.e., introducing antenna branch cross-correlation or cross polarization discrimination (XPD) are presented.

Supporting PACS on a GSM MSC

Abstract: The Personal Access Communications System (PACS) is one of the ANSI air interface standards developed for the 1.9 GHz PACS band in the U.S. It is a low-tier standard that has been optimized for both indoor wireless access and low mobility pedestrian outdoor usage. The Global System for Mobile Telecommunications (GSM) system is widely deployed in Europe and Asia and is being considered for many other regions around the world. A natural evolution path for PCS would be one that combined the advantages of the PACS with readily available GSM networking capabilities. This paper addresses solutions to interfacing a PACS radio system to a GSM or GSM derivative (PCS1900 or DCS 1800) network at the GSM A-interface.

Performance and electromagnetic compatibility analysis of antennas for hand held mobile telephones

Abstract: The Finite Integration Algorithm (FIA) is used for the analysis of the Monopole and Radiation-Coupled Dual-L (RCDLA) antennas for personal communications at the GSM frequency of 900 MHz. The two aspects investigated are the electromagnetic-compatibility (EMC) and the performance. Special attention is given to a user wearing glasses, whereby the eddy currents in the frame induce electromagnetic fields in the eye area which is the very sensible area in the human head. It is found that 44% of the power delivered to the monopole is absorbed by the user, compared to only 20% for the RCDLA. The maximal local SAR (Specific Absorption Rate) inside the head for a transmitted power of 1 W for the monopole and RCDLA is 2 mW/cm3 and 0.9 mW/cm3 respectively. This is just reaching the German safety standard (2 mW/cm3 averaged over 10 g) for the monopole, but is less than half this standard for the RCDLA. It is also found that the RCDLA has a bandwidth of only 55 M.Hz, and that the user's hand has a strong influence on its resonant frequency. The monopole, on the other hand has a large bandwidth, and its impedance is not so sensitive to the presence of the user. For a user wearing glasses with a metalic frame, an increase of 2 dB in the local SAR in the area of the eye close to the phone is found compared to a user without glasses.

Comparative Numerical Study of Antennas for Hand Held Mobile Telephones.

Abstract: The Finite Integration Algorithm (FIA) is used for the analysis of monopole and Radiation-Coupled Dual-L (RCDLA) antennas for personal communications at the GSM frequency of 900 MHz. It is found that 44% of the power delivered to the monopole is absorbed by the user, compared to only 20% for the RCDLA. The maximal local Specific Absorbtion Rate SAR inside the head for a transmitted power of 1 W for the monopole and RCDLA is 2 mW/cm 3 and 0.9 mW/cm 3 respectively. It is also found that the RCDLA has a bandwidth of only 30 MHz, and that the user's hand has a strong influence on its resonant frequency. The monopole, on the other hand has a large bandwidth, and its impedance is not so sensitive to the presence of the user.