Doppler FFT | momoiot

Doppler FFT

1. Configuration

Parameter	Sub-Parameter	Option	Rec. Value	Description
2DFFT Cmpt. Size		8, 32 64, 128		FFT size
2DFFT Win	Start			Window start index
2DFFT Win	Length			Window length
Window Function		Hamming, Hanning, Blackman		Window function type
2DFFT Col	Offset			Column offset
2DFFT Col	Num			Number of columns
2DFFT Row	Offset			Row offset
2DFFT Row	Num			Number of rows
Range Gate Num				Number of range gates
Gate Range				Gate range
Min Target Energy				Minimum target energy (filter)

2. Data Output

When Doppler FFT data SPI output mode is selected by chip configuration command, the chip will output Doppler FFT data.

The data communication SPI operates in 32-bits format.

The data frame starts from the header Dword (32 bits); then all the Doppler FFT data are sent out,

with the high 16 bits represent real part of the FFT data, and the low 16 bits represent imaginary part;

finally, the tail Dword (32 bits) will valid the checksum and terminate the data output.

The data output is MSB first and the Doppler FFT data type is signed integer.

ICL1112/ICL111A

구분	필드명	Dword	Bit Range	설명
Header	Fixed Pattern	Dword 0	[31:24]	1010 1010
Header	Reserved	Dword 0	[23]	0
Header	Fixed Pattern	Dword 0	[22:20]	100
Header	DFFT_chirp_index	Dword 0	[19:11]	Chirp sequence number (frame 내, 0부터 시작)
Header	DW_LEN	Dword 0	[10:0]	Doppler FFT data count (0부터 시작)
Data	DFFT_real_data[0]	Dword 1	[31:16]	Doppler FFT real part (signed)
Data	DFFT_imag_data[0]	Dword 1	[15:0]	Doppler FFT imaginary part (signed)
Data	DFFT_real_data[1]	Dword 2	[31:16]	Doppler FFT real part (signed)
Data	DFFT_imag_data[1]	Dword 2	[15:0]	Doppler FFT imaginary part (signed)
Data	DFFT_real_data[n]	Dword …	[31:16]	Doppler FFT real part (signed)
Data	DFFT_imag_data[n]	Dword …	[15:0]	Doppler FFT imaginary part (signed)
Data	DFFT_real_data[m-1]	Dword m	[31:16]	Doppler FFT real part (signed)
Data	DFFT_imag_data[m-1]	Dword m	[15:0]	Doppler FFT imaginary part (signed)
Tail	Check_sum	Dword m+1	[31:16]	Doppler FFT data checksum (low 16bit sum 결과)
Tail	FFT_FRAME_INDEX	Dword m+1	[15:12]	Frame counter (0부터 시작)
Tail	Reserved	Dword m+1	[11:10]	0
Tail	CFG_MSG	Dword m+1	[9:8]	User defined bits
Tail	Fixed Pattern	Dword m+1	[7:0]	0101 0101