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add particulars for traffic control and boat radar ppi

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Mark Allyn
2026-05-21 10:04:44 -07:00
parent f71aab6abb
commit 52a3691bcf
1 changed files with 263 additions and 23 deletions
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CLAUDE.md
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@@ -191,17 +191,21 @@ These are knobs on the panel once that is built. Keyboard keys until then
overall sensitivity - keyboard q for lower; w for higher overall sensitivity - keyboard q for lower; w for higher
4. STC Range - range to which sensitivity to closer targets is effective 4. STC Range - range to which sensitivity to closer targets is effective
keyboard e for lower; r for higher keyboard e for lower; r for higher
5. Radiogoniometer knob for Chain Home; keyboard t for left turn; y for right turn. 5. Noise filter for rain noise. This is for the ppi scopes. keyboard t for decrease filtering and y
6. Maximum Range for all scopes except for chain home, which is fixed. This control to increase filtering
6. Radiogoniometer knob for Chain Home; keyboard u for left turn; i for right turn.
7. Maximum Range for all scopes except for chain home, which is fixed. This control
will not operate for Chain Home. These maximum will not operate for Chain Home. These maximum
range selections will be defined for each scope; If you try to go beyond the stated range selections will be defined for each scope; If you try to go beyond the stated
maximum ranges, the control will have no effect; note that the default maximum range would maximum ranges, the control will have no effect; note that the default maximum range would
be the highest for that scope; keyboard u for lower; i for higher be the highest for that scope; keyboard o for lower; p for higher
7. Range Cursor (for ppi scopes, not for a scopes) keyboard o for lower; p for higher 8. Range Cursor (for ppi scopes, not for a scopes) keyboard a for lower; s for higher
8. Bearing Cursor (for all ppi scopes; not for a scopes) 9. Bearing Cursor (for all ppi scopes; not for a scopes)
keyboard a for counterclockwise s for clockwise keyboard d for counterclockwise f for clockwise
9. Bearing for Marine A Scope. This is not for a cursor, but this operates the motor 10. Bearing for Marine A Scope. This is not for a cursor, but this operates the motor
that revolves the antenna unit keyboard d for counterclockwise and f for clockwise that revolves the antenna unit keyboard g for counterclockwise and h for clockwise
11. Noise filter for rain noise. This is for the ppi scopes. keyboard j for decrease filtering and k
to increase filtering
Notes; I am maintaining control separation between radiogon, marine a scope bearing, and ppi bearing. Notes; I am maintaining control separation between radiogon, marine a scope bearing, and ppi bearing.
However, when I make the control panel, those will be combined as one physical knob with three However, when I make the control panel, those will be combined as one physical knob with three
@@ -593,6 +597,150 @@ Individual scope informations
3. **Sweep Intersect Envelope:** Energy returns climb from the noise floor, achieve peak voltage 3. **Sweep Intersect Envelope:** Energy returns climb from the noise floor, achieve peak voltage
at perfect cross-coincidence, and fade back down into the receiver noise as the sweep line passes the target. at perfect cross-coincidence, and fade back down into the receiver noise as the sweep line passes the target.
Very important note on PPI radars: Definition of the 'top of the scope' and the graticule:
For a marine traffic control center radar, the top of the scope or 0 degrees is true north.
It does not move sice the control center radar does not move.
for a boat, the top of the scope is the bow of the boat (where are you heading). The zero
degrees on the graticule is still true north. The graticule is rotated by a small motor that
is tied to the boat's gyro compass. This allows the instinctive behavior of the skipper to
look forward by looking at the top of the scope.
Another importand note. The circular sweep on the scopr is clockwise. The degree ticks on the
graticule count clockwise from true north.
Note on blooming. If the signal on the grid of the crt is too great, the
brightness will no longer increase, but there will be a slight blooming of
the target.
This is suggested example psudeo code for the target shader
for both the radar equation as well as the blooming
Note that values will change depending on the scope being used (traffic control or boat)
-------------------------------------------------------------------
// Fragment Shader snippet for a single radar return
uniform float user_gain; // 0.0 to 1.0
uniform float selected_range; // e.g., 6.0 Nautical Miles
// Target attributes passed in or looked up from a texture/buffer
struct RadarTarget {
float range; // Distance from radar center
float azimuth; // Angle in radians
float RCS; // Radar Cross Section
};
void main() {
// Current fragment coordinates in Polar space
float frag_range = current_fragment_range();
float frag_azimuth = current_fragment_azimuth();
// 1. Calculate raw received power via Radar Equation
float R4 = pow(RadarTarget.range, 4.0);
float P_r = (Pt * G_squared * lambda_squared * RadarTarget.RCS) / (pow(4.0 * 3.14159, 3.0) * R4 * L);
// 2. Apply the 1960s Logarithmic IF Amplifier compression
float V_echo = log(1.0 + P_r * 1000.0);
float V_total = user_gain * V_echo;
// 3. Dynamic Blooming Coefficients
// As V_total exceeds 1.0 (saturation), expand the search/paint radius
float saturation = max(0.0, V_total - 1.0);
float dynamic_range_width = baseline_pulse_width + (0.05 * saturation);
float dynamic_azimuth_width = baseline_beamwidth + (0.02 * pow(saturation, 2.0));
// 4. Compute Distance from current fragment to the true target center
float d_range = abs(frag_range - RadarTarget.range);
float d_azimuth = abs(frag_azimuth - RadarTarget.azimuth);
// 5. Evaluate a Gaussian blur shape using the bloomed dimensions
float radial_paint = exp(-pow(d_range / dynamic_range_width, 2.0));
float azimuth_paint = exp(-pow(d_azimuth / dynamic_azimuth_width, 2.0));
float final_intensity = V_total * radial_paint * azimuth_paint;
// Clamp to CRT max brightness
gl_FragColor = vec4(final_intensity * phosphor_color, 1.0);
}
------------------------------------------------------------------------------------
=====================================================================================
PPI Radar Equiation
===================================================================================
For vessel traffic control radar:
Transmitter Peak Power - float transmitter_peak; 25.0 KW
Frequency - float frequency; 9.375 GHZ
Wavelength - float wavelength; 0.032 meters
Receiver Noise Figure - float nf; 11 dB
System Losses - flost sl; 8 dB
Antenna Beam Width - float beamwidth; 0.7 degrees
Pulse width - float pulsewidth; 0.1 microsecond
Pulse Rep Rate lookup table based on selected maximum range - float prf;
1.5 nm range PRF 3500. HZ
6 nm range PRF 2000. HZ
12 nm range 1000. HZ
Radar Antenna Rotation Rate float antenna_rpm; 15 RPM
Receiver gain notes:
Raw gain is about 100 dB
However the gain is logarithmic. It compressed the massive dynamic range
of real-world echoes so that a giant ship and a small wooden fishing
boat could both be visible on the CRT at the same time without the operator
constantly riding the gain knob.
The operator would turn the Gain knob up until the background
of the CRT just started to fill with a faint, shimmering, dancing
texture of fine static sparks (often called "grass" or "receiver noise").
If the gain was too low, weak echoes from distant targets or small
fiberglass boats in Bellingham Bay wouldn't have enough voltage
to overcome the CRT's grid cutoff, leaving them completely invisible.
If the gain was too high, the screen would "blossom" with solid white noise,
blinding the operator entirely.
======================================================================
For Polce or coast guard boat radar:
Transmitter Peak Power - float transmitter_peak; 15.0 KW
Frequency - float frequency; 9.375 GHZ
Wavelength - float wavelength; 0.032 meters
Receiver Noise Figure - float nf; 11 dB
System Losses - flost sl; 8 dB
Antenna Beam Width - float beamwidth; 1.2 degrees
Pulse Rep Rate lookup table based on selected maximum range - float prf;
1.0 nm range PRF 4000. HZ
3 nm range PRF 3000. HZ
6 nm range 1000. HZ
Pulse width - float pulsewidth; 0.1 microsecond
Radar Antenna Rotation Rate float antenna_rpm; 25 RPM
Receiver gain notes:
Raw gain is about 100 dB
However the gain is logarithmic. It compressed the massive dynamic range
of real-world echoes so that a giant ship and a small wooden fishing
boat could both be visible on the CRT at the same time without the operator
constantly riding the gain knob.
The operator would turn the Gain knob up until the background
of the CRT just started to fill with a faint, shimmering, dancing
texture of fine static sparks (often called "grass" or "receiver noise").
If the gain was too low, weak echoes from distant targets or small
fiberglass boats in Bellingham Bay wouldn't have enough voltage
to overcome the CRT's grid cutoff, leaving them completely invisible.
If the gain was too high, the screen would "blossom" with solid white noise,
blinding the operator entirely.
=====================================================================
Graticules - These are plastic overlays over the face of the scope. They are Graticules - These are plastic overlays over the face of the scope. They are
for the purposes of showing the bearing. They are calibrated in degrees; short line (1/8 inch) for the purposes of showing the bearing. They are calibrated in degrees; short line (1/8 inch)
each degree; medium line (1/4 inch) for every 5 degrees; and a longer line (1/2 inch) for every each degree; medium line (1/4 inch) for every 5 degrees; and a longer line (1/2 inch) for every
@@ -600,29 +748,121 @@ Individual scope informations
Notes that these graticule lines are lit by a #47 incandescent bulb #FFB347. Notes that these graticule lines are lit by a #47 incandescent bulb #FFB347.
There are text numeric values for every 15 degreen
There are two rings
The bearing ticks are on the inside of the outer ring.
The numeric degree values are between the outer and inner rings.
The innter ring is the boundry for active targets and the sweep.
======================================================================= =======================================================================
================================== ==================================
End of discussion
==================================
settings.h file suggestions: settings.h file suggestions:
/* Radar Hardware Constants */ /*
* MIT License
* * Copyright (c) 2026 Mark Allyn
* * Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
* * The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
* * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
* * Author: Mark Allyn
*/
#pragma once
#include <string>
/* =========================================================================
DEBUGGING AND SIMULATION SWITCHES
========================================================================= */
#define DEBUG_DISABLE_P7_PERSISTENCE 0 /* 1 = Bypass long persistence tracking for raw debugging */
#define DEBUG_DISABLE_TERRAIN 0 /* 1 = Hide landMASS rendering to isolate target processing */
#define GL_DEBUG_OUTPUT_ENABLED 1 /* 1 = Attach robust driver-level diagnostic callbacks */
/* =========================================================================
HISTORICAL COLOR PALETTES (HEX EMBEDDINGS)
========================================================================= */
/* A-Scope Graticule Backlights & Incandescent Pilot Bulbs */
#define HEX_COLOR_PILOT_LAMP 0xFFB347 /* #FFB347 - Warm Incandescent Glow */
/* A-Scope Mono-Phosphor Trace Colors */
#define HEX_COLOR_ASCOPE_EXCITATION 0x39FF14 /* #39FF14 - Vibrant Phosphor Flash */
#define HEX_COLOR_ASCOPE_AFTERGLOW 0x004400 /* #004400 - Darker Green Decay Base */
/* P7 Phosphor Color Pipeline States for PPI Radars */
#define HEX_COLOR_P7_EXCITATION 0xA0CFFF /* #A0CFFF - Bright Blue Active Beam Flash */
#define HEX_COLOR_P7_IMMEDIATE_BLUE 0x1010FF /* #1010FF - Post-Beam 1ms Decay Core */
#define HEX_COLOR_P7_SHORT_TERM_YG 0xE2FF80 /* #E2FF80 - Yellow Green 1s Persistent State */
#define HEX_COLOR_P7_LONG_TERM_AMBER 0xFFA040 /* #FFA040 - Amber 10s Deep Remembrance */
#define HEX_COLOR_P7_EXPIRATION 0x050700 /* #050700 - Near-Black Expiration Threshold */
/* GUI Core Color Specifications */
#define HEX_COLOR_TEXT_WHITE 0xFFFFFF
#define HEX_COLOR_TEXT_RED 0xFF0000
#define HEX_COLOR_TEXT_PINK 0xFFC0CB
#define HEX_COLOR_TEXT_YELLOW 0xFFFF00
/* =========================================================================
HARDWARE ENVIRONMENT MATRICES
========================================================================= */
namespace ChainHome { namespace ChainHome {
const float PEAK_POWER = 500000.0f; // 500 KW const float PEAK_POWER = 500000.0f; /* 500 KW */
const float WAVELENGTH = 12.0f; // 12 Meters const float WAVELENGTH = 12.0f; /* 12 Meters */
const float ANTENNA_GAIN = 3.16f; // 5 dB expressed as linear gain const float ANTENNA_GAIN = 3.16f; /* 5 dB expressed as linear gain */
const float PULSE_WIDTH = 0.000020f; // 20 microseconds const float PULSE_WIDTH = 0.000020f; /* 20 microseconds */
const float BEAM_WIDTH = 150.0f; // in degrees (large floodlight) const float BEAM_WIDTH = 150.0f; /* floodlight sector in degrees */
const float PRF = 25.0f; // pulse repetition rate in times per second const float PRF = 25.0f; /* Pulse Repetition Frequency (Hz) */
const float MAX_RANGE_METERS = 321868.0f; /* Fixed 200 Miles */
} }
namespace MarineAScope { namespace MarineAScope {
const float PEAK_POWER = 500000.0f; // 500 KW const float PEAK_POWER = 500000.0f; /* 500 KW */
const float WAVELENGTH = 0.10f; // 10 cm const float WAVELENGTH = 0.10f; /* 10 cm */
const float ANTENNA_GAIN = 1000.0f; // 30 dB expressed as linear gain const float ANTENNA_GAIN = 1000.0f; /* 30 dB linear gain conversion */
const float PRF = 500.0f; // pulse repetition frequency const float PRF = 500.0f; /* 500 Hz pulse repetition */
const float HORIZONTAL_BEAMWIDTH = 2.5f; // horizontal beamwidth const float HORIZONTAL_BEAMWIDTH = 2.5f; /* degrees */
const float SYSTEM_TEMPERATURE = 290.0f; // system temperature const float SYSTEM_TEMPERATURE = 290.0f; /* Kelvins (Ts) */
const float NOISE_FIGURE = 20.0f; // for period receivers; this is in Db const float NOISE_FIGURE = 20.0f; /* Early receiver noise figure in dB */
const float BOLTZMANN_CONSTANT = 1.38e-23f; const float BOLTZMANN_CONSTANT = 1.38e-23f; /* (k) Joules/Kelvin */
}
namespace MarineTrafficPPI {
const float PEAK_POWER = 25000.0f; /* 25.0 KW */
const float FREQUENCY_HZ = 9.375e9f; /* 9.375 GHz */
const float WAVELENGTH = 0.032f; /* 0.032 meters (3.2 cm X-Band) */
const float NOISE_FIGURE = 11.0f; /* 11 dB */
const float SYSTEM_LOSSES = 8.0f; /* 8 dB */
const float HORIZONTAL_BEAMWIDTH = 0.7f; /* 0.7 degrees razor-sharp */
const float PULSE_WIDTH = 0.1e-6f; /* 0.1 microseconds */
const float ANTENNA_RPM = 15.0f; /* 15 RPM mechanical rotation rate */
}
namespace MarineBoatPPI {
const float PEAK_POWER = 15000.0f; /* 15.0 KW tactical marine */
const float FREQUENCY_HZ = 9.375e9f; /* 9.375 GHz */
const float WAVELENGTH = 0.032f; /* 0.032 meters (3.2 cm X-Band) */
const float NOISE_FIGURE = 11.0f; /* 11 dB */
const float SYSTEM_LOSSES = 8.0f; /* 8 dB */
const float HORIZONTAL_BEAMWIDTH = 1.2f; /* 1.2 degrees */
const float PULSE_WIDTH = 0.1e-6f; /* 0.1 microseconds */
const float ANTENNA_RPM = 25.0f; /* 25 RPM high-frequency sweep */
} }