Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Doubt related to gsm modem antenna

Status
Not open for further replies.

adi_rage

Newbie level 6
Joined
Jul 14, 2011
Messages
12
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,360
I am using GSM MODEM provided by sim300 and i have no clue regarding the antenna specifications of the antenna used in this modem.
In the pdf file it is just mentioned that the module has 50db antenna connector.I do not know anything about this antenna connector and in what way it is related to the GSM modem antenna.?
 

WimRFP

Advanced Member level 5
Joined
Apr 16, 2010
Messages
1,591
Helped
594
Reputation
1,176
Reaction score
536
Trophy points
1,393
Location
Netherlands
Activity points
15,026
Hello,

It means that you have to connect an antenna (or antenna with cable) to the modem that is designed for a 50 Ohms impedance. In other words, you rmodem likes to see a more ore less 50 Ohms load to be happy. 50 Ohms is almost the standard reference impedance in RF telecom and measurement. By the way, video and cable distribution uses 75 Ohms.

The documentation should tell you what type of connector (socket) is used, as you need this to get the right plug to make the connection. there may also be solder pads close to the socket that can be used for direct cable connection (that means you have to solder).
 

adi_rage

Newbie level 6
Joined
Jul 14, 2011
Messages
12
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,360
Actually my doubt is,here in gsm modem what type of antenna are we using las we have some types like dipole antenna,helical antenna etc..
 

WimRFP

Advanced Member level 5
Joined
Apr 16, 2010
Messages
1,591
Helped
594
Reputation
1,176
Reaction score
536
Trophy points
1,393
Location
Netherlands
Activity points
15,026
To give you useful feedback: can you give us info w.r.t. external or internal antenna, plastic/metal case, size of case, available space for antenna, other (metallic) structures very close to the modem, external antenna via certain length of cable, etc.

If you have metallic case, an external quarter wave antenne can do the job when the ground of the antenna is directly connected to the case.
 

adi_rage

Newbie level 6
Joined
Jul 14, 2011
Messages
12
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,360
Antenna of the modem is connected via a brown colour wire which is ended in a connector of MMCX then for this connector,antenna is connected and is enclosed in samll black colour conical shaped plastic casing so what type of antenna is this?
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top