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7

First of all, in refering to standard specification, please mention the version because the numeration between versions can be different. My answer should be only a comment but I think with images it would be easier for you. Everything in my answer is for 36.211 v8.7.0. The section 5.6 SC-FDMA baseband signal generation and 6.12 OFDM baseband signal ...


6

System Frame Number (SFN) is really just a counter. As its name, it tells us the index of system frame modulo 1024, the index is from 0 to 1023 (10 bits). SFN does not help the physical synchronization (frequency carrier, DFT starting frame, pilots, ...) because it is the information obtained after the waveform synchronization. It is decoded in Master ...


5

If you are refering to "E-UTRA operating bands" defined by 3GPP standands (section 5.5), the answer is NO. In LTE access network, an operating band is assigned to a physical cell and MIMO is a signal processing method in the band. Currently, MIMO in LTE uses frequency between sub-carriers and space diversity (SFBC, spatial multiplexing and beamforming) and ...


5

You are mixing two things modulation and multiple access. SC-FDMA has been chosen because it is battery-friendly modulation. SC-FDMA is used in both FDD and TDD modes. There are several reasons why both FDD and TDD are defined. Historically, people want to utilize efficiently the precious spectrum. FDD needs two bands while TDD needs only one. ...


3

This answer is for LTE standard, not 5G NR. However I do believe that the basic concept does not change since. (Logical) Antenna port is defined formally as in 3GPP 36.211 An antenna port is defined such that the channel over which a symbol on the antenna port is conveyed can be inferred from the channel over which another symbol on the same antenna ...


3

Some more disadvantages: Channel estimation using pilots is harder, because you do not have orthogonal data on each frequency bin, compared to OFDM. That's why e.g. LTE uplink resorts to a midamble for channel estimation in uplink Application of non-linear MIMO detection algorithms is harder (i.e. more complex), because you essentially have coupled MxM ...


2

There's a lot of different domains of knowledge coming together here, so I'll split my answer into multiple sections, each answering an implicit question that you raise in your explicit question. Hope that helps! Can your RTL-Dongle actually receive at 1.72 GHz? So, first the bitter pill: There's a lot of sellers out there that offer RTL dongles and claim ...


2

One possible answer is given at the beginning of the text: Raleigh suggested and later proved that the processing required by MIMO at higher speeds would be most manageable using OFDM modulation, because OFDM converts a high-speed data channel into a number of parallel lower-speed channels. Also: MIMO-OFDM is a particularly powerful combination ...


2

The only portion of the spectrum that is "occupied" or "transmitted" are the subcarriers that are actually used (i.e. 10 MHz instead of 15 MHz). The null subcarriers referenced in your question are used for two purposes: The null subcarriers along the edges are used to allow for easily-realizable anti-aliasing filters. Given a sample rate of 15.36 MHz (...


1

Operating frequency of an antenna is not related to whether it's a single antenna or in MIMO configuration. Operating frequency is related to the geometry of the antenna. The antenna is designed to be optimal in delivering and radiating power in that frequency. MIMO is a mathematical method to put the signal of interest on the antennas in such a way that ...


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