HSDPA Alongside A CS Voice Call

Back a year ago I noticed that an incoming circuit-switched voice call during a 3.5G HSDPA packet-switched data session forced the packet connection to go back to 64 kbit/s dedicated bearer while the call was ongoing. After the call the bearer was upgraded to 384 kbit/s but was only put back on the High Speed Shared Channels once the download was finished. Looks like the software on the network side has advanced a bit in the meantime as I recently noticed that even during a phone call an ongoing download continued at HSDPA speeds. Very nice!

Note: The test a year earlier was performed in the German Vodafone network while my latest observation is from the Orange France network. The RAN vendors might not necessarily be the same and it's even likely that they are not.

2 thoughts on “HSDPA Alongside A CS Voice Call”

  1. The first HSDPA solution our vendor offered didn’t support CS + PS at all! A couple of years later we can set up a CS call in parallel with HSDPA and EUL or even a VT call. I think at the time a lot of people thought that HSDPA would be a data product only technology (hence no support for CS in parallel) but of course as we all know it is very popular with handsets now.

  2. Hi Martin,

    I have a query on this CS+PS in HSDPA capable cell.
    Why it was not supported at first? Now how it is supporting CS+PS parallel in HSDPA cell?
    What are the 3GPP specs mentioned about this?
    Does HSDPA supports Soft/SofterHO in this CS+PS case?

    Thanks in adv,

Comments are closed.