forked from JiaoXianjun/GNSS-GPS-SDR
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Raw GPS signal samples data set for testing GPS receivers.html
91 lines (75 loc) · 2.48 KB
/
Raw GPS signal samples data set for testing GPS receivers.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<head>
<title>Raw GPS signal samples data set for testing GPS receivers</title>
<style>
body {
margin: 0;
background: #fff url(cherokee-images/default-bg.png) center center repeat-y
}
#S3sep13 {
margin: auto;
text-align: center;
width: 800px;
max-width: 800px;
border: 1px solid #fff;
}
.F3sep13 {
font-family: 'Trebuchet MS', 'Lucida Grande', Verdana, Arial, Sans-Serif;
background-color: #e6e6fa;
color: #000;
padding: 10px;
margin-top: 80px;
font-size: 120%;
text-align: left;
}
.img {
display: block;
margin-left: auto;
margin-right: auto;
}
code {
font-weight: bold;
}
.powered {
margin: 40px;
text-align: center;
}
</style>
</head>
<body>
<div id="S3sep13">
<div class="F3sep13">
<p style="font-size:20px"><b>Raw GPS signal samples data set for testing GPS receivers</b></p>
<p>
3-Sep-2013
<br><br>
Raw GPS signal sample data can be a little hard to find on the net. Here is a 56 MB file containing about 77 seconds of data:
<a href="https://dl.dropboxusercontent.com/u/68809050/gps.samples.1bit.I.fs5456.if4092.bin"> gps.samples.1bit.I.fs5456.if4092.bin</a> [dropbox.com] <br>
It was copied and re-formatted from Michele Bavaro's excellent GPS blog, although the file is not there now:
<a href="http://michelebavaro.blogspot.com/2010_11_01_archive.html">
michelebavaro.blogspot.com</a>
</p>
<p>
The parameters of the file are: 1-bit sign I-only data (not I&Q, not 2 or 3-bit sign & magnitude), bit-packed Little Endian (i.e. start with bit 0 of byte 0), sample rate fs = 5.456 MHz, IF = 4.092 MHz (i.e. not a zero-IF signal -- you have to mix (xor) with 4.092 MHz in addition to the C/A code). As Michele's post mentions if your decoding works you should get a lat/lon position in Nottingham, UK.
</p>
<p>
I used this file as input to a software simulation I wrote of the FPGA tracking parts of Andrew Holme's wonderful homemade GPS receiver documented here:
<a href="http://www.aholme.co.uk/GPS/Main.htm"> aholme.co.uk/GPS
</a>
</p>
<p>
Just using Andrew's FFT-based C++ search code alone immediately finds five signals:
</p>
<p>
SV-0 PRN-1 lo_shift 6 ca_shift 1465 snr 108.7 <br>
SV-20 PRN-21 lo_shift 8 ca_shift 686 snr 121.7 <br>
SV-28 PRN-29 lo_shift -9 ca_shift 3868 snr 167.2 <br>
SV-29 PRN-30 lo_shift -9 ca_shift 2998 snr 145.2 <br>
SV-30 PRN-31 lo_shift -8 ca_shift 2337 snr 121.3
</p>
</div>
</div>
<br>
</body>
</html>