5 Replies Latest reply on Dec 3, 2013 9:00 PM by jasonrc

# WICED Wi-Fi Driver [WWD] controls radio TX power?

How can a customer control the TX power of the radio?

Is this part of the WICED Wi-Fi Driver?

Given PA power dominates power draw during transmit, for battery powered applications adjusting TX power can increase battery life.

Ive looked for TX Power control and related [e.g. RSSI] in WICED/SDK, but havent found much.

Thanks,

Phil
• ###### 2. Re: WICED Wi-Fi Driver [WWD] controls radio TX power?
Thank you!    :)
• ###### 3. Re: WICED Wi-Fi Driver [WWD] controls radio TX power?
Phil, unless your app transmits a metric shedload, receive dominates power consumption by a loooooong way, NOT transmit.

Power consumption is all about "integrating the area under the curve"

Energy to transmit a 1ms packet at 350mW = 350uJ

Energy to run a receiver for 1s at 60mW = 60mJ

Make sense?

Plus, the power saved by dropping RF Tx power is not net necessarily that much.

It depends on the class of power amplifier used.
• ###### 4. Re: WICED Wi-Fi Driver [WWD] controls radio TX power?

Ive got a customer using WICED as follows.

1.  WICED is in AP mode

2.  WICED TXs a 4 byte packet to STA

3.  WICED RXs a 540 byte packet from STA.

Steps 2 & 3 repeat so long as the WICED radio is on.  This mode dominates the use case.  The radio never TXs more than 4 bytes.  The radio never RXs more than 540 byte packets.

[ratio of TX to RX is 1 to 135 ]

The thought was that given the TX is 7x the RX that turning down the power would help.  [Generally the two radios are close - at arms length literally.]

Ignoring whatever the WICED needs to do in STA mode, the use case mirrors what you mention i.e. RX dominates.

The current solution [K60 + AR6103] has average power of 58 mA @ 3.3v.  The customers goal is 1/3 better i.e. 38 mA.

Most of the means to save power assume radio is STA arent they [i.e. sleep.]  Given the above use case, please suggest current saving techniques.  If these can be easily demonstrated to the customer, all the better.

Thanks,

Phil
• ###### 5. Re: WICED Wi-Fi Driver [WWD] controls radio TX power?
There is no general powersaving techniques for an Access Point unfortunately.

The AP receiver must remain on permanently to receive packets asynchronously from associated clients.

The Wi-Fi Direct standard provides some powersaving techniques for a Wi-Fi Direct Group Owner.

These are not currently implemented in WICED.