Supplementary Downlink (SDL)

Hi Experts,
Is there any feature in Huawei like SDL feature in Ericsson?
Supplementary Downlink.

Never knew there was SDL.
What is SDL for?
Carrier aggregation?

Yes, for CA.
It will barry specific carrier to do anything except CA.

1 Like

For Nokia, it’s possible:

Supplementary Downlink in which a frequency band is used for downlink-only traffic to support a conventional band running both uplink and downlink. Most LTE networks today use paired spectrum where both uplink and downlink are given a dedicated spectrum block allocated of the same size. Simply put, Supplementary Downlink enhances a network’s downlink capacity as well as the users’ experiences. Essentially, it gives significantly faster downloads and supports a much greater number of users with mobile devices.

For example, the downlink only band can use the L-band (1452-1492 MHz), which was previously used as a broadcast band for terrestrial and satellite DAB in Europe. It could also be considered in other bands.

Using Supplementary Downlink allows operators to avoid the costs of investing in additional base station and backhaul infrastructure - once mobile broadband demand exceeds network capacity, networks can be easily expanded by deploying a 1.4 GHz Supplementary Downlink on existing base station sites.

Supplementary Downlink and carrier aggregation have been enabled in standards from HSPA+ Release 9 and LTE Release 10. Nokia has for some time offered Supplementary Downlink radios for the two most common bands, Band 29 for North America and the 1.4 GHz L-Band standardized as band 32 in 3GPP and harmonized in Europe. The 1.4 GHz Supplementary Downlink L band, when paired with low frequency spectrum such as 800 MHz, offers similar propagation characteristics as sub-1 GHz because the uplink, which is the limiting factor for coverage, is only carried on 800 MHz, while 1400 MHz is only used for the downlink. The Supplementary Downlink radios offer additional downlink link capacity and receivers, resulting in 4RX diversity for the primary band (for example 800 MHz in Europe) to deliver better service quality, in particular better indoor coverage.


In Ericsson it is CXC4011567, name = SUPPLEMENTARYDLONLYCELL, productType = Baseband

Is there any feature in Huawei like this dear?

Not sure about Huawei.