GSM frequency bands

About: GSM frequency bands is a research topic. Over the lifetime, 559 publications have been published within this topic receiving 5067 citations.

Adaptive antennas in frequency hopping GSM

Abstract: The combination of adaptive antennas and the GSM frequency hopping option has been investigated. The results show that large advantages can be made by combining adaptive antennas and frequency hopping. Interference diversity is always obtained independent of traffic load and features like discontinuous transmission and power control. Frequency hopping also improves the ability for the adaptive antenna system to track the mobiles. Further, frequency hopping GSM networks employing adaptive antennas can be planned for very tight frequency reuse. A 3 cell reuse plan can be fully loaded and it is even possible for a network planned for 1 cell reuse to handle up to 70% channel utilization according to system level simulations.

A triple band antenna for GSM and GPS application

Abstract: We report a dual-feed microstrip antenna for operation in the GSM 900/1800 MHz bands and GPS 1575 MHz band. The GPS antenna is right circularly polarized whereas the GSM antenna is linearly polarized. Simulation and measured results are presented for return loss and isolation. An isolation of better than -33dB between the two feed points has been achieved. The overall ground plane size is seen to be smaller than that for a triple-band PIFA design.

Design of Single-Turn Spiral Inductors With Embedding A Strong-Coupling LC Resonator for Interference Suppression

Abstract: This paper presents a study on the interference suppression effect of a resonator-embedded spiral inductor topology. In the proposed topology, a conventional single-turn spiral inductor is integrated with an embedded strong coupling ${LC}$ resonator on a printed circuit board. This ${LC}$ resonator can be designed with a specific resonant frequency near but below the operation band to achieve interference suppression by way of redirecting the magnetic flux emitted from the spiral inductor to the resonator, rather than toward the other spiral inductors outside around. In this paper, the design of interference suppression is mainly demonstrated at the LTE 700-MHz band. From the experimental results in a contrast case, the interference at 700 MHz can be depressed more than 20 dB by the proposed topology as referred to a conventional spiral inductor. The proposed topology can provide a design freedom in any interested frequency bands, such as the popular GSM bands (900/1800 MHz) or ISM bands (2.4 GHz), by changing the capacitance value of the resonator. To verify the interference suppression effect resulted from the proposed topology, electromagnetic simulations and experimental measurements in both frequency domain and time domain are conducted to provide the more in-depth view.

Design and testing of rectifying antenna for RF energy scavenging in GSM 900 band

Abstract: The energy scavenging techniques are found as sustainable solution to the increasing energy needs. The increased use of wireless devices and installation of cell phone towers in the recent years produces abundant radio frequency (RF) energy in the ambient environment. This makes the RF energy scavenging as an attractive possibility. The energy scavenging module consists of an antenna to capture RF energy and appropriate circuitry for RF to DC conversion. In the present work, a microstrip-fed printed shorted ring slot antenna with circular polarization is chosen for collecting RF energy. The bridge rectifier with Schottky diode is used for RF to DC conversion. The novelty of the work lies in the design of a highly efficient yet simple and compact rectenna module for energy harvesting in the GSM 900 band using circularly polarized antenna. The antenna structure is designed and optimized using CST microwave studio. The bridge rectifier circuit is designed using SPICE software. The measured results fo...

A multiple–shape channel selection filter for multimode zero–IF receiver using capacitor over active device implementation

Abstract: In this paper, a base-band first stage filter for a 3G multimode zero-IF receiver is presented. The multiple-shape channel selection filter can be configured either in a W-CDMA or GSM/DCS mode, by a simple digital command. The structure is a third order Butterworth low-pass filter, implemented using the Gm-C technique. The equivalent input thermal noise is 26nV/√Hz for the GSM mode and 36nV/√Hz for the W-CDMA mode; the out-of-band IIP3 is 5.3dBvp and 4.7dBvp for the GSM and W-CDMA modes respectively. The in-band IIP1 is -1dBvp and -3dBvp for the GSM and W-CDMA modes respectively. The circuit consumes 1.9mA in the GSM mode and 450µA in the W-CDMA mode. The whole structure was implemented in a 0.25µm SiGe BiCMOS process with 2fF/µm2MIM capacitors permitting integration with a 3G multi-mode zero-IF receiver. This base-band circuit was layed out using capacitors over active devices implementation, in order to permit an important reduction of the die area.