Understanding WLAN and GPS Circuit on Smart Phones

Additional features such as Bluetooth, WLAN and GPS on Smart phones become more popular in the market. As a techie you also need to figure out how this circuit works in order for you to catch up a new evolving designed on mobile  phones.

These additional features is packed into an IC component module in a circuit, and this kind of
of circuit are associated with a master clock which typically a external clock crystal oscillator.
With the master clock the data transmitted or received  is modulated to a proper certain frequency.

Here's how simply tells us how the circuit works on smart phones.

The WLAN circuit
 Wireless Local Area Network (WLAN) links two or more devices using some wireless distribution method (typically spread-spectrum or OFDM  radio), and usually providing a connection through an access point to the wider internet. This gives users the mobility to move around within a local coverage area and still be connected to the network.

A typical block diagram below shows bluetooth wlan circuit, this block diagram will tell us how the clock oscillator feeds desired frequency to the WLAN module. The Wlan is associated is with the bluetooth transceiver circuit to send receive the data from the Wlan module to register it to the application processor.
In this diagram shows that the WLAN module also needs the RF clock to make it work, this RF clock comes from the RF circuit. In other designed aVoltage Controlled Temperature Compensated Crystal Oscillator(VCTXO) is used as an external clock generator.

Typical block diagram of Bluetooth WLAN circuit

The GPS Circuit
The Global Positioning System (GPS) is a space-based global navigation satellite system that provides reliable location  and time information in all weather and at all times and anywhere on or near the Earth when and where there is an unobstructed line of sight to four or more GPS satellites.The GPS (global positioning system) circuit comes with a GPS module this is packed into chip, a GPS RX filter, GPS clock crystal oscillator and a GPS antenna.
In this block diagram the GPS module is being feed with different RF clock data signal which also comes from the RF circuit.

Typical block diagram of bluetooth with WLAN and GPS circuit

The components layout of Bluetooth, WLAN and GPS circuit on a PCB board.
This shows an example of the bluetooth circuit associated with WLAN and GPS circuit mounted on PCB board.

You'll figure out that all circuit components such as the ic oscillator, bluetooth chip, wlan chip and gps chip is mounted all together with each corresponding connections. The RF clock is  located on the RF circuit section which is comes from the RF chip.


And here's an schematic diagram of WLAN and GPS circuit, for knowing how the circuit components connected with each corresponding components.

This  is only a simple explanation how does the circuit works, the main key for this lesson is how to figure out and used this tutorial in troubleshooting and repairing GPS and WLAN problem and failures on a particular mobile phone devices, that we are going to tackle it here and so on...

Posted in: Cell Phone Repair Tips