m17core/
shaping.rs

1pub static RRC_48K: [f32; 81] = [
2    -0.0031955054,
3    -0.002930098,
4    -0.001940547,
5    -0.00035607078,
6    0.0015469185,
7    0.003389342,
8    0.0047616027,
9    0.0053105336,
10    0.0048244493,
11    0.003297721,
12    0.00095865194,
13    -0.0017498062,
14    -0.00423843,
15    -0.005881418,
16    -0.006149877,
17    -0.0047450834,
18    -0.0017040828,
19    0.0025476913,
20    0.0072151264,
21    0.011230345,
22    0.013421123,
23    0.012729687,
24    0.008449026,
25    0.00043672565,
26    -0.010734711,
27    -0.023725418,
28    -0.03649577,
29    -0.04649801,
30    -0.0509759,
31    -0.04733776,
32    -0.03355284,
33    -0.008513286,
34    0.027694825,
35    0.07365995,
36    0.1266812,
37    0.18297966,
38    0.23806532,
39    0.28721792,
40    0.3260201,
41    0.35087407,
42    0.35943073,
43    0.35087407,
44    0.3260201,
45    0.28721792,
46    0.23806532,
47    0.18297966,
48    0.1266812,
49    0.07365995,
50    0.027694825,
51    -0.008513286,
52    -0.03355284,
53    -0.04733776,
54    -0.0509759,
55    -0.04649801,
56    -0.03649577,
57    -0.023725418,
58    -0.010734711,
59    0.00043672565,
60    0.008449026,
61    0.012729687,
62    0.013421123,
63    0.011230345,
64    0.0072151264,
65    0.0025476913,
66    -0.0017040828,
67    -0.0047450834,
68    -0.006149877,
69    -0.005881418,
70    -0.00423843,
71    -0.0017498062,
72    0.00095865194,
73    0.003297721,
74    0.0048244493,
75    0.0053105336,
76    0.0047616027,
77    0.003389342,
78    0.0015469185,
79    -0.00035607078,
80    -0.001940547,
81    -0.002930098,
82    -0.0031955054,
83];
84
85#[cfg(test)]
86mod test {
87    use std::f32::consts::PI;
88
89    #[test]
90    fn calculate_rrc_coefficients() {
91        let mut rrc = [0.0; 81];
92        let roll_off = 0.5;
93        let t_s: f32 = 10.0;
94
95        let inf_t = t_s / (4.0 * roll_off);
96
97        for i in 0..81 {
98            let t = (i as isize - 40) as f32;
99
100            if t == 0.0 {
101                rrc[i] = 1.0 / t_s.sqrt() * ((1.0 - roll_off) + (4.0 * roll_off / PI));
102            } else if t == inf_t || t == -inf_t {
103                rrc[i] = roll_off / (2.0 * t_s).sqrt()
104                    * ((1.0 + 2.0 / PI) * f32::sin(PI / (4.0 * roll_off))
105                        + (1.0 - 2.0 / PI) * f32::cos(PI / (4.0 * roll_off)));
106            } else {
107                rrc[i] = 1.0 / t_s.sqrt()
108                    * (f32::sin((PI * t * (1.0 - roll_off)) / t_s)
109                        + (4.0 * roll_off * t) / t_s * f32::cos((PI * t * (1.0 + roll_off)) / t_s))
110                    / (PI * t / t_s * (1.0 - (4.0 * roll_off * t / t_s).powi(2)));
111            }
112        }
113
114        println!("{:?}", rrc);
115        for (a, b) in rrc.iter().zip(super::RRC_48K.iter()) {
116            assert!((a - b).abs() < 0.00001);
117        }
118    }
119}
m17core/shaping.rs

m17core/
shaping.rs
