OFDM Demodulation

OFDM demodulation.

blockType: OFDMDemodulation

Path in the library:

/5G/OFDM Demodulation

Description

Block OFDM Demodulation evaluates the synchronization offset to the strongest SS block using the PSS reference sequence (NID2). After correcting the frequency offset, it is assumed that the central frequencies of the reference PSS and the received signal have aligned, after which the block OFDM Demodulation demodulates the synchronized signal and extracts the SS block.

The block performs the following actions:

Creates a reference grid for estimating time using the detected PSS. The PSS is placed in the second character of the OFDM reference grid, since the first character of the OFDM contains a special length of the cyclic prefix.
Evaluates the synchronization offset relative to the OFDM symbol to the detected SSB based on the contents of the reference grid.
Performs synchronization, OFDM demodulation, and extraction of the strongest SS block.

Configuring the block includes setting the following parameters:

Setting the frequency range Block Pattern: FR1: Case A, Case B, Case C, FR2: Case D, Case E.
Setting the number of transmitted information blocks Bitmap of SS blocks transmitted: 4, 8, 64.
Setting the distance between subcarriers Subcarrier spacing (kHz): 15 kHz or 30 kHz for FR1, 60 kHz or `120 kHz' for FR2.
Setting the minimum channel bandwidth for the NR range Minimum channel bandwidth for the NRb (MHz) `5 MHz', `10 MHz', `40 MHz'.

Ports

Entrance

Nid — detected PSS sequence (NID2) in the received pass signal:q[<br>] scalar

The detected PSS sequence (NID2) in the received signal.

Data type: Float64

CorWfm is a frequency—shifted signal in the form of a complex matrix
matrix

A frequency-shifted signal returned as a complex matrix.

Data type: ComplexF64

Output

ResGrid is a demodulated output signal in the form of a complex matrix
matrix

The demodulated output signal returned as a complex matrix.

Data type: ComplexF64

Parameters

Main

Block Pattern — ID of the pass frequency range:q[<br>] Case A | Case B (default) | Case C | Case D | Case E

For the 5G standard, the frequency range used is specified in the documentation.

Frequency range designation Frequency range

Frequency range designation	Frequency range
FR1: `Case A`,`Case B`,`Case C`	410 MHz – 7125 MHz
FR2: `Case D`,`Case E`	24250 MHz – 52600 MHz

FR1: Case A,Case B,Case C

410 MHz – 7125 MHz

FR2: Case D,Case E

24250 MHz – 52600 MHz

Programmatic use
Block parameter	`BlockPattern`
Values	`Case A` \| `Case B` \| `Case C` \| `Case D` \| `Case E`
By default	`Case B`

Bitmap of SS blocks transmitted — number of transmitted blocks of pass information:q[<br>] 4 | 8 (default) | 64

The number of transmitted information blocks.

Programmatic use
Block parameter	`TransmittedBlocks`
Values	`4` \| `8` \| `64`
By default	`8`

Subcarrier spacing (kHz) — distance between subcarriers in kHz
15(default) | 30 | 60 | 120

The distance between subcarriers in kHz for all channels and carrier reference signals.

The values to select are 15 or 30 for FR1, 60 or 120 for FR2.

Programmatic use
Block parameter	`SubcarrierSpacingCommon`
Values	`15` \| `30` \| `60` \| `120`
By default	`15`

Minimum channel bandwidth for the NRb (MHz) — setting the minimum channel bandwidth for the NR band in MHz
5 (default) | 10 | 40

Setting the minimum channel bandwidth for the NR band in MHz.

Programmatic use
Block parameter	`MainChannelBW`
Values	`5` \| `10` \| `40`
By default	`5`

Links

Glossary: Standard 5G