Wavecom WISMO Quik Q2501, Руководство по дизайну для клиентов

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WM_PRJ_Q2501_PTS_002 - 001
March 2004
confidential ©
Page: 54 / 79
This document is the sole and exclusive property of WAVECOM. Not to be distributed or divulged
without prior written agreement.
Ce document est la propriété exclusive de WAVECOM. Il ne peut être communiqué ou divulgué à
des tiers sans son autorisation préalable.
0.5 dB can be considered as a maximum value for loss between the
module and an external connector.
3.5.2 GSM/GPRS antenna connection
3.5.2.1 Antenna specifications
The GSM/GPRS antenna must fulfil the requirements given in the table
hereafter.
A dual-Band antenna will work in these frequency bands and must have the
following characteristics:
Characteristics E-GSM 900 DCS 1800
Frequency TX 880 to 915 MHz 1710 to 1785 MHz
Frequency RX 925 to 960 MHz 1805 to 1880 MHz
Impedance 50 Ohms
Rx max 1.5 : 1
VSWR
Tx max 1.5 : 1
Polarization Linear
Typical radiated
gain 0 dBi in one direction at least
Note:
WAVECOM recommends a VSWR max. of 1.5:1 for the Rx and Tx.
Nevertheless, all aspects of this specification will be fulfilled even with a
VSWR max. of 2:1 for the Rx and the Tx.
the DC impedance presented by the GSM/GPRS connection is floating.
Nevertheless, there is no problem when using antennas that present a
short to ground.
GSM antenna providers:
Refer to paragraph 9.6.