Can a DSS Cell carry 30 kHz Subcarriers or it has to be 15 kHz?

I can’t get this info from anywhere…

Can a DSS Cell carry 30 kHz Subcarriers or it has to be 15 kHz? (As DSS is a resource with LTE)

Based on this article can use 15Khz…


DSS implementation techniques

Backward compatibility is at the core of the DSS concept. Today, there are many LTE devices in use, making it impossible for operators to modify the LTE transmission. The sharing of LTE and NR must be transparent to LTE devices and NR transmission must adapt to coexist with LTE.

LTE transmission uses 15-kHz subcarrier spacing, while NR can use 15- or 30-kHz subcarrier spacing. Initial DSS deployments use 15-kHz subcarrier spacing. NR becomes orthogonal with LTE when using 15-kHz subcarrier spacing because it uses the same time and frequency grid. This is not the case when NR uses 30-kHz subcarrier spacing, though. Yet LTE and NR still share the same time and frequency resources from the network perspective, requiring user equipment (UE) capable of decoding the combined LTE and NR transmission. Legacy LTE devices must decode the LTE signal just as in the traditional LTE network, and NR devices must decode the NR signal. A device that supports both needs the capability to decode both signals simultaneously.

When using 30-kHz subcarrier spacing, NR will occupy twice as much bandwidth in the frequency domain, but half of the duration in the time domain. Mixed numerology causes interference, breaking the orthogonality. Using a guard band to separate assignments in the frequency domain avoids such interference. Time multiplexing also achieves this goal by separating the two transmissions in the time domain

Link for your reference…hope this answered your query…

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Normally we are using 15-kHz subcarrier spacing in FDD and 30-kHz subcarrier spacing in TDD for 5G SA.

No, DSS has to be 15 kHz.