How is Dynamic Spectrum Sharing (DSS) being implemented?

Hi All,
Can anyone shed light on Dynamic Spectrum Sharing (DSS)?
I heard its throughput is less than 4G or 5G.
Then why its required?
Can anyone also refer any link how DSS is actually implemented by various MNOs in PHY layer?
Any of these DSS related changes will have any impact on L2 layer protocols?


It’s required to introduce 5G services when spectrum is scarce.


  1. To smoothly convert current LTE carrier -> LTE+NR -> NR Only
  2. To have good NR coverage.

But DSS has given very negative results for MNOs in USA.

Can 5G be introduced in existing 4G spectrum without explicit 5G Spectrum auction by respective country governments?
DSS can be achieved through various options.
Any link how various MNOs across the globe have implemented it so far?
Like Verizon, T-Mobile, AT&T, Telus, etc.

  1. It is kind of spectrum sharing of current LTE bands for 5G services.
  2. It can be helpful in areas where certain LTE bands are scarcely used and can be utilized for 5G services instead of being SCell for LTE services.
  3. This can be considered as an easy and economic way to move to 5G.

I read a good article at edn, have a look at it, if it helps: Dynamic spectrum sharing implementation challenges and solutions

Regarding why DSS Sucks in US, because LTE with higher CA was providing better services and consumers expect drastic change in Throughput with 5G :wink:

This is my uderstanding.

I think it depends on regulatory.
If the neutrality frequency is permit, it’s possible to use frequency bands 4G in 5G.

To the point :+1:t2:

This is absolutely correct.
Because of this Verizon lost root metric test.

Thanks and yes that’s my understanding too.:pray:

Thanks it is a good read indeed. :slightly_smiling_face:

There are mainly 2 ways:

  1. Subframe Split Based Sharing (MBSFN subframes)
  • Shared resources limited to MBSFN subframes
  • NR DL channels are supported only in MBSFN configured subframes
  • Sharing can be TDM (with NR in MBSFN subframes; Rel 8/9) or FDM (both, NR and LTE in MBSFN subframes; Rel 10+)
  1. Channel Puncturing Based
  • Puncturing NR CSI-RS, TRS, SSB, SIB
  • CRS rate-matching
  • RB rate-matching (scheduling avoidance) for LTE-SSS/PSS/PBCH
  • FDM and TDM
  • Several variants exist

Well elaborated!

One more point:

  1. Low Band NR with DSS, can help to extend coverage of 5G Mid-Band via CA of NR-NR.

But definitely it is little risky, as already all expressed especially customer perception of 5G, because with 5G logo, one will be getting less throughput then 4G. Also some capacity get compromised.

Good for operators with Low Band LTE (800, 900, 1800, 2100) with surplus capacity to introduce 5G for continuous 5G coverage layer between Mid-Band and Low Band.