PSS Search and Frequency Offset Correction
PSS search and frequency correction.
blockType: PSSSearchandFrequencyOffsetCorrection
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Path in the library: |
Description
Block PSS Search and Frequency Offset Correction receives the 5G downlink signal of the NR baseband at the input and performs a PSS search and a rough estimate of the frequency offset by performing the following steps:
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The frequency shift of the received signal to the intended frequency shift. The estimated shifts are located at a distance of half of the subcarrier frequency from each other.
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Comparing the frequency-shifted received signal with each of the three possible PSS sequences (NID2) and extracting the strongest correlation peak. The reference PSS sequences are frequency-centered. Therefore, the strongest correlation peak provides a measurement of the rough frequency offset relative to the center frequency of the carrier. The peak also indicates which of the three PSS sequences (NID2) was detected in the received signal and the time point of the best channel condition.
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Estimating the frequency offset below half of the subcarrier by comparing the cyclic prefix of each OFDM symbol in the SSB with the corresponding useful parts of the OFDM symbols. The phase of this correlation is proportional to the frequency shift in the signal.
Configuring the block includes setting the following parameters:
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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):
15kHz or30kHz for FR1,60kHz or120kHz for FR2. -
Setting the minimum channel bandwidth for the NR range Minimum channel bandwidth for the NRb (MHz)
5MHz,10MHz,40MHz.
Ports
Input
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Wfm
—
the 5G-NR signal in the time domain in the form of a complex matrix
the matrix
Details
The 5G NR signal in the time domain, returned as a complex matrix. The number of columns of the matrix corresponds to the number of transmitting antennas.
| Data types |
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| Complex numbers support |
No |
Output
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Nid
—
detected PSS sequence (NID2) in the received signal
scalar
Details
The detected PSS sequence (NID2) in the received signal.
| Data types |
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| Complex numbers support |
No |
#
SSBoff
—
frequency shift value
scalar
Details
The value of the frequency shift.
| Data types |
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| Complex numbers support |
No |
#
CorWfm
—
a frequency-shifted signal in the form of a complex matrix
the matrix
Details
The frequency offset of the signal returned as a complex matrix.
| Data types |
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| Complex numbers support |
No |
Parameters
Main
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Block Pattern —
id of the frequency range
Case A | Case B | Case C | Case D | Case E
Details
For the 5G standard, the frequency range used is specified in the documentation.
| Frequency range designation | Frequency range |
|---|---|
FR1: |
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FR2: |
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| Values |
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| Default value |
|
| Program usage name |
|
| Tunable |
No |
| Evaluatable |
No |
#
Bitmap of SS blocks transmitted —
number of transmitted information blocks
4 | 8 | 64
Details
The number of transmitted information blocks.
| Values |
|
| Default value |
|
| Program usage name |
|
| Tunable |
No |
| Evaluatable |
No |
#
Subcarrier spacing (kHz) —
the distance between subcarriers in kHz
15 | 30 | 60 | 120
Details
The distance between subcarriers in kHz for all channels and carrier reference signals.
Values to choose from: 15 or 30 for FR1, 60 or 120 for FR2.
| Values |
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| Default value |
|
| Program usage name |
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| Tunable |
No |
| Evaluatable |
No |
#
Minimum channel bandwidth for the NRb (MHz) —
setting the minimum channel bandwidth for the NR band
5 | 10 | 40
Details
Setting the minimum channel bandwidth for the NR band.
| Values |
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| Default value |
|
| Program usage name |
|
| Tunable |
No |
| Evaluatable |
No |