I have decided to use Antenova product which is M20057 (datasheet) as an active GPS antenna. I am using Quectel L96 GNSS module.

There is an internal chip antenna on L96 module and I have tried the performance of L96 without M20057-1 before. I can get location data while the device is outdoors but we couldn't get the location data at indoors. That's why I have decided to use an active antenna to improve performance.

I have just received the PCB with M20057 and I am not able to get the location data either indoors and outdoors with M20057-1. It is obvious that there is a problem with the design of the printed circuit board.

I don't know whether the problem is the matching circuit (does it affect the performance that much,) layout, or schematic.

Could you please review my schematic and layout to check if is there a problem?

I know that it quite hard to detect the problem in this way but even your approaches might be pretty useful.

I am going to share screenshots of schematics and layout.


I would like to give so more detail about the design. I have uploaded two ss to describe how I think during designing the circuit. For L96 Anton pin has been designed for decreasing active antenna power consumption. Anton pin is only pulled high when the module is high. I haven't used the Anton pin. I am using pnp mosfet circuit as a high side switch to control the power consumption of GPS module so I connect the same supply to the active antenna in this way when the module is closed active antenna is also closed.

L96 Example design

Please check the pin description and application circuit of M20057 it is written that AT1 should be connected to the ground.


In my design, there are matching elements on the circuit but I haven't soldered them. After seeing this pin description I have made a short circuit AT1 and AT2 to ground. I thought that was the problem but it changed nothing. So I am literally stuck.

  • \$\begingroup\$ I think you are on your own with this. The M20057 data sheet isn't accessible without jumping through hoops. \$\endgroup\$ – Andy aka Nov 12 '19 at 12:09
  • \$\begingroup\$ @Andyaka: I added a link to the datsheet on Digikey - no dolphin acts needed. I'm afraid it doesn't help much though. At least not for me. I don't see anything in it that would help here. \$\endgroup\$ – JRE Nov 12 '19 at 12:16
  • \$\begingroup\$ Is the keep-out area correct? \$\endgroup\$ – Andy aka Nov 12 '19 at 12:30
  • \$\begingroup\$ Also, why is RF_OUT disconnected, when it is connected to RF_IN in the reference design? \$\endgroup\$ – Richard the Spacecat Nov 12 '19 at 13:31
  • \$\begingroup\$ @RichardtheSpacecat In the datasheet, It is written that there is a 0 ohm resistor between RF_IN and RF_OUT. However, it will be soldered only if you use the internal antenna. That's why there is no connection between RF_IN and RF_OUT. I will check it again \$\endgroup\$ – Caner Adıyaman Nov 12 '19 at 13:48

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