Recently while delivering a training, I realised that this is a topic that I haven't covered in the blog before, even though I have been talking about it for a while. FeICIC has been introduced in Release-11 and there are a few enhancements as shown above. The main being that instead of an Almost Blank Subframe (ABS) with no other information except for the reference signals, now there is a possibility of reduced power ABS where the data on PDSCH can still be transmitted but on a reduced power level. This would ensure that the capacity of the interferer is not wasted.
Another enhancement on which FeICIC depends on are the advanced receivers (should do a post on it sometime soon). Another feature that allows a better probability of reception is the Transmission Mode 9 (TM9 - see blog post here)
An interesting comment that I received on my Deployments Dilemma Post is also relevant to the discussion here:
The ground reality is generally a lot different than theory. Metrocells often face interference not just from Macrocells but also other Metrocells. The ABS patterns are not just straightforward Macro to pico case but even pico to pico and multiple macros to pico.
Until all the handsets and other dongles could be upgraded with advanced interference cancellation receivers, there would be many scenarios where deployment option 2 may be chaotic. Deployment option 1 can serve the users well in the meantime.
We can sacrifice efficiency for reliability in the meantime.
I recently posted the Small Cells Research Bible on the Small Cells blog here, the following is the Interference Management part that would help anyone willing to learn more about this feature.
I think reduced-power ABS had been proposed in R10. However, this document said reduced-power ABS was introduced in R11. Why?
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