Panasonic EB-GD90, Техническое руководство

Страница: 9 / 38

http://cxema.ru
RF OVERVIEW
MCUK990801G8 Section 3 Issue 1
Technical Guide – 7 – Revision 0
3 RF OVERVIEW
3.1 Introduction
3.1.1 General Specifications
GD90 is a Dual Band product incorporating two switchable transceivers, one for the GSM900 band and another for the
GSM1800 (DCS1800) band. The transmit and receive bands for the mobile are given in the table below:
Other salient technical features are as follows:
3.1.2 Description of Main PCB
All components required for the RF and Logic circuits, excluding the LCD module and backlight LEDs, are contained on the
Main PCB. The Main PCB has six layers made from FR4 material (Epoxide woven glass fabric copper-clad laminate as
specified in BS4584 Part 102 and prepeg as specified in BS4584 Part 103). Top and bottom layer tracks are gold-plated to
prevent oxidisation and enable better soldering. The board thickness is 0.9 mm (± 0.1 mm).
The RF components are located on both sides of the upper area of the Main PCB. To provide RF shielding, most of one side
of the Keypad PCB comprises a printed circuit groundplane. The Main board is connected to the Keypad PCB via a 34-way
dual in-line connector. A metallised plastic chassis is used to separate the Main and the Keypad PCB’s. When the chassis is
sandwiched between the Main and the Keypad PCB’s, the groundplane of the Main board together with the chassis forms an
effective shielded enclosure which prevents spurious emissions. The chassis has also been designed to provide smaller walled
sections which are used to isolate sensitive RF areas such as the VCTCXO and the VCO from high level interferers such as
the PA output.
3.2 Functional Description
3.2.1 Frequency Plan
The GD90 frequency plan is shown below
.
Tx Rx
GSM900 890-915 MHz 935-960 MHz
GSM1800 1710-1785 MHz 1805-1880 MHz
GSM900 GSM1800 Units
Rx Bandwidth 25 75 MHz
Tx Bandwidth 25 75 MHz
Duplex Spacing 45 95 MHz
Number of Channels 124 374
ARFCN (Channel Numbers) 1-124 512-885
1st Tx Channel 890.2 1710.2 MHz
Last Tx Channel 914.8 1784.8 MHz
1st Rx Channel 935.2 1805.2 MHz
Last Rx Channel 959.8 1879.8 MHz
Maximum Tx Power 33.0
(Class 4) (PL5) 30.0
(Class 1) (PL0) dBm
Minimum Tx Power 5.0
(PL19) 0.0
(PL15) dBm
Tx Tx IF RFLO Tx IFLO Tx Unit
GSM900 890-915 270 1160-1185 540 MHz
GSM1800 1710-1785 130 1580-1655 520 MHz
Rx Rx 1st IF Rx 2nd IF RFLO Rx IFLO Rx Unit
GSM900 935-960 225 45 1160-1185 540 MHz
GSM1800 1805-1880 225 45 1580-1655 540 MHz