UART Communication between GSM and GPS

[Aankur]

UART Communication between GSM and GPS

I want to establish a UART Communication between GSM and GPS.
The Supply Voltage of GPS is 3.3V.
The Supply Voltage of GSM is 3.8V.

The measured RX/TX Voltage Levels of GPS is 2.8V and 0V (for logic High and logic Low).
The measured RX/TX Voltage Levels of GSM is 1.8V and 0V (for logic High and logic Low).

Since there is a difference between RX/TX logic levels of the GSM and GPS, So I am
not able to establish the UART Communication between GSM and GPS.

I am using the interpreter of the telit GSM module to process the data of the GPS.
I am not using any micro-controller to in between the GSM and GPS.

Please suggest me a possible way to perform voltage (or Logic) level shifting.

[MadScientist]

A simple transistor circuit on the relevant Tx lines will do the job