Subcarrier frequency

There are usually at frequencies of 5.8, 6.2, or 6.8 MHz (the video carrier usually resides below 5 MHz on a satellite transponder or microwave relay). Extra subcarriers are sometimes transmitted at around 7 or 8 MHz for extra audio (such as radio stations) or low-to-medium-speed data.

1. Why 15 KHz subcarrier in LTE?
2. What is meant by carrier frequency?
3. Why only 12 subcarriers in LTE?
4. What is subcarrier spacing?

Why 15 KHz subcarrier in LTE?

Simply, It is because 3G and LTE have the same clock timing for multi technology handsets.

What is meant by carrier frequency?

The proportion of individuals in a population who have a single copy of a specific recessive genetic variant. Carrier frequency also sometimes refers to the prevalence of variants in dominantly acting genes, such as BRCA1 and BRCA2. Also called carrier rate.

Why only 12 subcarriers in LTE?

In the downlink, the subcarriers are split into resource blocks. This enables the system to be able to compartmentalise the data across standard numbers of subcarriers. Resource blocks comprise 12 subcarriers, regardless of the overall LTE signal bandwidth. They also cover one slot in the time frame.

What is subcarrier spacing?

Subcarrier spacing is equal to the reciprocal of the symbol time. As a result of the longer symbol time, the subcarrier size and spacing decreases from 312.5 KHz to 78.125 KHz. The narrow subcarrier spacing allows better equalization and therefore enhanced channel robustness.