Intercarrier Interference BWP and First/last OFDM Symbol of a Slot

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Hello,
I am using a slightly modified version of creating downlink carrier waveform (important changed parameters below) . I have only data from PDSCH here
I have observed 2 things:
1)If I look closer into the first plot, I can see that there is a interference between the subcarriers: the slightly blueish resource elements in the spectroram. Is there a way to eliminate/reduce this effect?
Because I actually would like to use 2 bandwidth parts which are basically glued together and have no zeros between them(for measurements).
2) If I zoom into the plot, I can see that the first OFDM Symbol of the "green" bandwidth part has got constant values, which seem unusual,since it is only in the green BWP and does not exist in the yellow one. I would assume that this is the symbol which is used for Cyclic Prefix, but that would still not explain the constant value of it.
My changed parameters are: only pdsch, no pdcch, ssburst etc
scscarriers{1}.SubcarrierSpacing = 15;
scscarriers{1}.NSizeGrid = 106;
scscarriers{1}.NStartGrid = 0;
bwp{1}.SubcarrierSpacing = 15; % BWP subcarrier spacing
bwp{1}.CyclicPrefix = 'Normal'; % BWP cyclic prefix for 15 kHz
bwp{1}.NSizeBWP = 45; % Size of BWP
bwp{1}.NStartBWP = 0;
pdsch{1}.SymbolAllocation = [0,14]; % First symbol and length
pdsch{1}.SlotAllocation =[1:10]; % Allocated slot indices for PDSCH sequence
pdsch{1}.Period = 15; % Allocation period in slots
pdsch{1}.PRBSet = [0:bwp{1}.NSizeBWP-1];
scscarriers{2}.SubcarrierSpacing = 30;
scscarriers{2}.NSizeGrid = 51;
scscarriers{2}.NStartGrid = 1;
bwp{2}.BandwidthPartID = 2; % Bandwidth part ID
bwp{2}.SubcarrierSpacing = 30; % BWP subcarrier spacing
bwp{2}.CyclicPrefix = 'Normal'; % BWP cyclic prefix for 30 kHz
bwp{2}.NSizeBWP = 21; % Size of BWP
bwp{2}.NStartBWP = 30;
pdsch{2}.BandwidthPartID = 2; % PDSCH mapped to 2nd BWP
pdsch{2}.SymbolAllocation = [0,13];
pdsch{2}.SlotAllocation = [2:20];
pdsch{2}.PRBSet = [0:bwp{2}.NSizeBWP-1];
coresets{1}.FrequencyResources = [0 0 0 0];
thank you for your help
  2 Comments
fatih özdemir
fatih özdemir on 4 Dec 2020
Upon closer inspection,
I see that the first and last symbol seems not to be modulated Plot shows only first and second symbol of a pdsch slot
fatih özdemir
fatih özdemir on 5 Jan 2021
Regarding 1) I found that this is a typical phenomenon and is called inter-numerology interference.

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