Skip to main content

MTN Ghana saves your battery with cDRX technology


In 4G LTE, cDRX lets the phone fall asleep, even while connected. 

cDRX stands for connected mode discontinuous reception. A device remains connected until there is inactivity for 5 seconds.

cDRX only works while connected. In the idle (disconnected) state, only a few features are available (refer to 3GPP TS 36.304). These features include: Taking measurements of the signal; receiving system information; notifying the network after moving into a different area; notifying the network of availability every 54 minutes; and connecting when there is something to do (call, text, or data). Every 0.32 seconds, a phone wakes up to listen for one of the towers in the area possibly requesting it to connect.

While the phone is asleep due to cDRX or otherwise, latency (lag) may occur. This isn't the only reason why it occurs.

What are the conditions required before a phone can fall asleep while connected (cDRX)?

Conditions vary. For example, here are results gathered during a test:

89.79% LTE_cDRX - short_drx_cycle:40, long_drx_cycle:320, on_duration_timer:10, inactivity_timer:200

5.37% LTE_cDRX - No config

1.70% LTE_cDRX - short_drx_cycle:80, long_drx_cycle:320, on_duration_timer:10, inactivity_timer:100

1.18% LTE_cDRX - short_drx_cycle:0, long_drx_cycle:40, on_duration_timer:2, inactivity_timer:30

0.79% LTE_cDRX - short_drx_cycle:40, long_drx_cycle:320, on_duration_timer:5, inactivity_timer:20

0.52% LTE_cDRX - short_drx_cycle:40, long_drx_cycle:40, on_duration_timer:2, inactivity_timer:30

0.39% LTE_cDRX - short_drx_cycle:40, long_drx_cycle:160, on_duration_timer:10, inactivity_timer:100

0.26% LTE_cDRX - short_drx_cycle:40, long_drx_cycle:320, on_duration_timer:200, inactivity_timer:200


What do these mean?

Here is a simplified and context-dependent explanation that does not replace correct explanations (including 3GPP TS 36.321, 3GPP TS 36.300, and 3GPP TS 36.331).

short_drx_cycle: Length of cycle initially used after inactivity, in milliseconds. There may be multiple short drx cycles before long drx cycles are used instead.

long_drx_cycle: Length of long cycle in milliseconds.

on_duration_timer: At the beginning of the cycle, stay awake for __ milliseconds.

inactivity_timer: After receiving instructions (data will be transferred), stay awake for __ more milliseconds.



What about the rest of the cDRX settings?

Those weren't gathered for the statistics above. Here are some of those:

onDurationTimer: psf10 (7)

drx-InactivityTimer: psf200 (15)

drx-RetransmissionTimer: psf2 (1)

longDRX-CycleStartOffset: sf320 (9)

  sf320: ...

shortDRX

  shortDRX-Cycle: sf40 (7)

  drxShortCycleTimer: 4 shortDRX-Cycles


onDurationTimer: psf10 (7)

drx-InactivityTimer: psf100 (14)

drx-RetransmissionTimer: psf8 (4)

longDRX-CycleStartOffset: sf320 (9)

  sf320: ...

shortDRX

  shortDRX-Cycle: sf80 (9)

  drxShortCycleTimer: 1 shortDRX-Cycle


onDurationTimer: psf2 (1)

drx-InactivityTimer: psf30 (9)

drx-RetransmissionTimer: psf2 (1)

longDRX-CycleStartOffset: sf40 (3)

  sf40: ..


And here are the other referenced settings that are not part of cDRX:

defaultPagingCycle: rf32 (0)

nB: oneT (2)


RRC/UE Inactivity Timer: 5 sec, estimated

T3412: 54 min


Some phones and modems may support long cDRX only, some phones and modems may not support cDRX at all.


All settings in this page are subject to change and/or may differ.

Popular posts from this blog

Unofficial list of 250+ Shortcodes (USSD) for MTN Ghana +updates

This page is not provided by nor affiliated with MTN Ghana, though it could be useful on MTN, and maybe other MNOs (AirtelTigo, Glo, Vodafone). It is not guaranteed to be complete or accurate. Request addition/removal below. Before dialing USSD codes, the mobile phone shall be within 2G or 3G coverage. If connected to 4G, the mobile phone shall be allowed to use 2G or 3G automatically, not "4G only" also known as "LTE only". In the event of only 4G being available, seek alternatives, including MyMTN. To the greatest extent possible, only the user is responsible for any unintended operation after use, including but not limited to "accidentally subscribing to premium services", try dialing *175# to unsubscribe. Use at your own risk. All trademarks are the property of their respective owners. Listing of a code does not imply endorsement. Do not pay anyone who claims that your code will be added to this page. No codes were added that way. Th...

MTN Ghana 216.47GB(or 182.08GB) for 399GHS, more details

This bundle is now removed from *138# and the MyMTN app, but there's 92.88GB for 350GHS. The purchase of 399GHS grants the user 216.47GB(now 214.09GB, after taking into account updated taxes 182.08GB) of data and a 50% bonus if bought on 4G . There is an additional 25% Terrific Thursday bonus if bought on Thursday. The 4G Bonus now requires that the bundle be bought with MobileMoney in the MyMTN app. Place the device on 4G and do not gift the bundle. It is OK if it temporarily switched to 3G or 2G during the use of *138# or *170#. If you are not given the 4G bonus, you will be given it later. Alternatively, contacting the network may have you granted the bonus earlier. Even without that, you'll eventually be given the bonus. Even if it's purchased with 4G, the bundle can be used on 3G or 2G. The bonus expires after 1 week, precisely 168 hours after purchase. Quite like how milk expires: after a week or so, you'll have to dispose of it all no matter how much is lef...

MTN Ghana VoLTE now available for some subscribers

MTN Ghana VoLTE now available for some subscribers Meaning of VoLTE VoLTE means Voice over LTE, and LTE can be explained as 4G. This means voice calls are possible on 4G, without having to rely on the temporary use of 3G or 2G during voice calls. Though WhatsApp could be used for voice calls on 4G even without VoLTE, VoLTE skips queues and can be better where the network is slow . VoLTE has a priority of 5 or 1, and data can have a priority of 6. WhatsApp does not skip queues. Improved call quality This is by using Adaptive Multi Rate Wideband at up to 23.85Kbps* instead of using Adaptive Multi Rate Wideband at up to 12.65Kbps. However, calls to AirtelTigo numbers, Glo numbers, and shortcodes are instead with Adaptive Multi Rate Narrowband at up to 12.2Kbps*. This includes shortcodes that play music. * Subject to change. Message There is a message associated with VoLTE. "Y'ello! You can now enjoy improved voice calls and data activities concurrently with the VoLTE service. To ...