Notecard Active GPS Antenna Option

We are from Embedded Design company based in San Jose having development Center in Chennai India. Currently we are designing prototype for one of automotive product to be used in US region for which we need tracking kind of application.
We want to know on the application circuit to be used for Active antenna. We want to know if any additional circuit is required for GPS Active Antenna or Notecard module has inbuilt circuitry for supplying power to the Active Antenna?
Is shorting the pins “VACT_GPS_OUT” and “VACT_GPS_IN” enough for using Active Antenna?

Hi @narendra and welcome to the Blues Wireless community!

To answer your question, yes, by shorting VACT_GPS_OUT and VACT_GPS_IN you can use an active GPS antenna with the Notecard. Please see here for our docs on the subject.

Another option is to use an active GPS antenna with our Notecarrier-B or Notecarrier-Pi models (docs here).

Let me know if I can answer any other questions for you!

Hi Roblauer,
Can you please confirm one more thing on this if voltage supplied(3.3V-4V) when VACT_GPS_OUT and VACT_GPS_IN are shorted is configurable in software or it can supply any voltage in this range? Most of active GPS antenna operates in the range 3-3.3V which is lower than the notecard module supplies so my question is can voltage be restricted to 3.3V?

2)I have another related question. How do we control sleep mode of the module. Is it SW controlled? I mean is there any way we can control module sleep mode like normal sleep mode, deep sleep mode etc.

Hi @narendra,

Great question. Most of the active GPS antennas we have used are in the 3-5v range (I just double checked the two active antennas I recently purchased, and they are both 3-5v). If a specific voltage is required outside of this range, you’ll have to supply your own regulated voltage to VACT_GPS_IN.

Hi Roblauer,
So you mean voltage at antenna pin can be any voltage in between 3.3V-4V and its not regulated? We have measured voltage and it reads about 3.9V.
Anyway We will be supplying power externally to it as our active antenna supports 3-3.3V.
Can you please also answer for the sleep mode implementation?

Correct - you need to supply regulated voltage to that pin.

Sorry, missed that sleep question! Check out our low power design guide. We talk about Notecard power management in depth there.

Thanks for your help, I will look into it.

Hi RobLauer,
We have tested GPS location with active Antenna by supplying 3.3V externally to VACT_GPS_INpin and we are able to get correct location. Thanks for your help.

I have another question on this. Many module support VBAT pin which can be used to supply power through external battery like coin cell which helps to retain the last searched satellite location faster especially when system is rebooted and it has to get the location. looking at notecard pinout there is no such pin available so i think this feature is not available. Am i correct?

Good to hear!

You’re correct that there is no VBAT pin available. However, we are looking into testing an external GNSS module that does have this capability. If you’d be interested in being part of this test, please send me a DM.

Hello…I have the apparatuses to introduce MCX, SMA and BNC connectors on this kind of little RG174 persuade utilized with these radio wires. Be that as it may, JonJay nailed it. The little parts are difficult to work with and 9 out of 10 of them require binding with an overly fine tipped patching iron in a little hole. You have better have a magnifier glass and zero hand shake (no espresso for you that day). Since these are dynamic recieving wires an awful connector establishment could short and broil something costly. In the event that you had a BNC end it would be simpler as there are twofold pleat connector alternatives not needing patching. Yet, yours seems, by all accounts, to be MCX.

Just adding a point of clarification. The 3.9V supplied by VACT_GPS_OUT is regulated on Notecard.

The expectation is many GPS antennas accept a range of bias voltages to power the low noise amplifier (LNA). If you have specific voltage requirements, please do supply it via VACT_GPS_IN

The VACT_GPS_OUT is offered for convenience.