Altec GSM SOCKET AL7020S - Manual (Page 28)

AL7020S, AL7024S Designer’s Guide
Doc. No. DG_7024E Altec Electronic AG Seite 28 / 32
5.1.5 RF Antenna
Antenna sub-system and integration in the application is a major issue.
Attention should be paid to :
• Choice of the antenna cable (type, length, performance, thermal resistance, etc)
• Antenna connector (type + losses). These elements could affect GSM
performances such as sensitivity and emitted power
• The antenna should be isolated as much as possible from the digital circuitry
(including the interface signals)
• It is strongly recommended to shield the terminal.
• On terminals including the antenna, a poor shielding could dramatically affect the
sensitivity of the terminal. Moreover, the power emitted through the antenna could
affect the application.
Warning:
Altec Electronic strongly recommends to work with an antenna manufacturer either
to develop an antenna adapted to the application or to adapt an existing
solution to the application. The antenna adaptation (mechanical and electrical
adaptation) is one of the key issues in the design of a GSM terminal.
The antenna-cable and the antenna should be as far as possible away from other
circuitry, specially switching-regulators, analog- and uC digital circuits. It is
recommended to place the antenna-jack near a metal enclosure and go through this
one with the antenna-cable.
5.2 Manufacturing Considerations
The Socket Modem has been designed to be mounted onto the host board in one of
two ways.
The first method consists of soldering two 32-pin strip sockets to the host board and
inserting the Socket Modem into the sockets. A suggested part number for the 32-pin
socket is Sam Tec SMM-132-01-F-S.
The second way is to solder the Socket Modem directly to the host board. The most
efficient way to do this is through a wave solder process. The recommended hole size
for the Socket Modem pins is 0.036 in. ±0.003 in. in diameter. Spacers can be used to
hold the Socket Modem vertically in place during the wave solder process. A spacer
should be placed on pin 32 and pin 64 of the Socket Modem. A suggested part
number for the spacer is BIVAR 938-0.130 for P1(0.310in) option Socket Modems.
The spacers can be left on permanently and will not effect operation.
Socket Modems can be put through a water wash process.