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Finally Noise Signal with best option 16 bit LFSR

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This commit is contained in:
Brumi-2021 2023-05-02 21:29:35 +02:00
parent 804fa0d3c4
commit d77102426a
3 changed files with 26 additions and 30 deletions
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12
firmware/application/apps/ui_siggen.hpp
View File

@ -48,17 +48,14 @@ private:
void update_tone();
void on_tx_progress(const uint32_t progress, const bool done);
const std::string shape_strings[10] = {
const std::string shape_strings[7] = {
"CW-just carrier",
"Sine signal ",
"Triangle signal",
"Saw up signal ",
"Saw down signal",
"Square signal ",
"Noise 8-nx20Khz", // using 8 bits LFSR register, 6 order polynomial feedback.
"Noise 8-nx10khz", // using 8 bits LFSR register, 7 order polynomial feedback.
"Noise 8 -nx5khz ", // using 8 bits LFSR register, 8 order polynomial feedback.
"Noise 16-nx1khz" // using 16 bits LFSR register, 16 order polynomial feedback.
"White Noise " // using 16 bits LFSR register, 16 order polynomial feedback.
};
bool auto_update { false };
@ -81,10 +78,7 @@ private:
{ &bitmap_sig_saw_up, 3 },
{ &bitmap_sig_saw_down, 4 },
{ &bitmap_sig_square, 5 },
{ &bitmap_sig_noise, 6 },
{ &bitmap_sig_noise, 7 },
{ &bitmap_sig_noise, 8 },
{ &bitmap_sig_noise, 9 }
{ &bitmap_sig_noise, 6 }
}
};

32
firmware/baseband/proc_siggen.cpp
View File

@ -61,21 +61,9 @@ void SigGenProcessor::execute(const buffer_c8_t& buffer) {
} else if (tone_shape == 5) {
// Square
sample = (((tone_phase & 0xFF000000) >> 24) & 0x80) ? 127 : -128;
} else if (tone_shape == 6) { // taps: 6 5; feedback polynomial: x^6 + x^5 + 1 , Periode 63 = 2^n-1,it generates armonincs n x 20Khz
// White Noise generator, pseudo random noise generator, 8 bits linear-feedback shift register (LFSR) algorithm, variant Fibonacci.
} else if (tone_shape == 6) { // White Noise generator, pseudo random noise generator, 8 bits linear-feedback shift register (LFSR) algorithm, variant Fibonacci.
// https://en.wikipedia.org/wiki/Linear-feedback_shift_register
bit = ((lfsr >> 2) ^ (lfsr >> 3)) & 1;
lfsr = (lfsr >> 1) | (bit << 7);
sample = lfsr;
} else if (tone_shape == 7) { // taps: 7 6; feedback polynomial: x^7 + x^6 + 1 , Periode 127 = 2^n-1,it generates armonincs n x 10Khz
bit = ((lfsr >> 1) ^ (lfsr >> 2)) & 1;
lfsr = (lfsr >> 1) | (bit << 7);
sample = lfsr;
} else if (tone_shape == 8) { //taps:8,6,5,4;feedback polynomial: x^8 + x^6 + x^5 + x^4 + 1,Periode 255= 2^n-1, armonics n x 5khz
bit = ((lfsr >> 0) ^ (lfsr >> 2) ^ (lfsr >> 3) ^ (lfsr >> 4)) & 1;
lfsr = (lfsr >> 1) | (bit << 7);
sample = lfsr;
} else if (tone_shape == 9) { // 16 bits LFSR .taps: 16, 15, 13, 4 ;feedback polynomial: x^16 + x^15 + x^13 + x^4 + 1
// 16 bits LFSR .taps: 16, 15, 13, 4 ;feedback polynomial: x^16 + x^15 + x^13 + x^4 + 1
// Periode 65535= 2^n-1, harmonics every < 1Khz , quite continuous .
if (counter == 0) {
bit_16 = ((lfsr_16 >> 0) ^ (lfsr_16 >> 1) ^ (lfsr_16 >> 3) ^ (lfsr_16 >> 4) ^ (lfsr_16 >> 12) & 1);
@ -87,6 +75,20 @@ void SigGenProcessor::execute(const buffer_c8_t& buffer) {
counter = 0;
}
}
/* else if (tone_shape == 7) { // 8 bit options, finally not used-
bit = ((lfsr >> 2) ^ (lfsr >> 3)) & 1; // taps: 6 5; feedback polynomial: x^6 + x^5 + 1 , Periode 63 = 2^n-1,it generates armonincs n x 20Khz
lfsr = (lfsr >> 1) | (bit << 7);
sample = lfsr;
} else if (tone_shape == 8) { // taps: 7 6; feedback polynomial: x^7 + x^6 + 1 , Periode 127 = 2^n-1,it generates armonincs n x 10Khz
bit = ((lfsr >> 1) ^ (lfsr >> 2)) & 1;
lfsr = (lfsr >> 1) | (bit << 7);
sample = lfsr;
} else if (tone_shape == 9) { //taps:8,6,5,4;feedback polynomial: x^8 + x^6 + x^5 + x^4 + 1,Periode 255= 2^n-1, armonics n x 5khz
bit = ((lfsr >> 0) ^ (lfsr >> 2) ^ (lfsr >> 3) ^ (lfsr >> 4)) & 1;
lfsr = (lfsr >> 1) | (bit << 7);
sample = lfsr; } */
if (tone_shape < 6) {
tone_phase += tone_delta;
@ -125,7 +127,7 @@ void SigGenProcessor::on_message(const Message* const msg) {
fm_delta = message.bw * (0xFFFFFFULL / 1536000);
tone_shape = message.shape;
lfsr = seed_value ; // init lfsr 8 bits.
// lfsr = seed_value ; // Finally not used , init lfsr 8 bits.
lfsr_16 = seed_value_16; // init lfsr 16 bits.
configured = true;

12
firmware/baseband/proc_siggen.hpp
View File

@ -42,13 +42,13 @@ private:
uint8_t tone_shape { };
uint32_t sample_count { 0 };
bool auto_off { };
int32_t phase { 0 }, sphase { 0 }, delta { 0 }; // they may have sign .
int8_t sample { 0 }, re { 0 }, im { 0 }; // they may have sign .
uint8_t seed_value = {0x56}; // seed 8 bits lfsr : any nonzero start state will work.
uint16_t seed_value_16 = {0xACE1}; // seed 16 bits lfsr : any nonzero start state will work.
uint8_t lfsr { }, bit { }; // bit must be 8-bit to allow bit<<7 later in the code */
uint16_t lfsr_16 { }, bit_16 { }; // bit must be 8-bit to allow bit<<7 later in the code */
int32_t phase { 0 }, sphase { 0 }, delta { 0 }; // they may have sign in the pseudo random sample generation.
int8_t sample { 0 }, re { 0 }, im { 0 }; // they have sign + and -.
uint16_t seed_value_16 = {0xACE1}; // seed 16 bits lfsr : any nonzero start state will work.
uint16_t lfsr_16 { }, bit_16 { }; // bit must be 16-bit to allow bit<<15 later in the code */
uint8_t counter {0};
// uint8_t seed_value = {0x56}; // Finally not used lfsr of 8 bits , seed 8blfsr : any nonzero start state will work.
// uint8_t lfsr { }, bit { }; // Finally not used lfsr of 8 bits , bit must be 8-bit to allow bit<<7 later in the code */
TXProgressMessage txprogress_message { };
};