L9 — Project 1 Work Day#
No new theory today. Your group is the survivability analysis cell supporting B-21 mission planning, and the period belongs to Project 1: detection range versus aspect and band, with uncertainty a planner can actually use.
The ask#
Produce the range at which each threat radar class first detects the B-21, as a function of aspect angle and operating band — with uncertainty. Everything you need is in L1–L8: the range equation, RCS, the IADS taxonomy, and \(S_{\min}\). Detection range is not a number — it’s a shape.
The scenario#
A notional adversary IADS sector defends the target area with the three radar classes from L7 — the same notional parameters as the L7 type-along, so your old code works here:
Class |
Band |
\(f\) |
\(P_t\) |
\(G_t = G_r\) |
\(S_{\min}\) |
|---|---|---|---|---|---|
EW |
UHF |
0.5 GHz |
2 MW |
25 dBi |
\(-140\) dBW |
ACQ |
S |
3 GHz |
1 MW |
30 dBi |
\(-130\) dBW |
TTR |
X |
10 GHz |
100 kW |
35 dBi |
\(-140\) dBW |
Free space, monostatic, detect at \(S \geq S_{\min}\). The full tasking, deliverables, and grading live in the handout — it is the authoritative document.
The RCS model#
B21_RCS_Table.csv gives notional B-21 RCS in dBsm at \(5^\circ\) aspect steps, nose to tail, in all three threat bands. Three rules:
Band matching. Each radar uses its own band’s column: EW → UHF, ACQ → S, TTR → X.
Symmetry. The table is symmetric about the nose–tail axis, so it covers the full circle.
Uncertainty. Every value is the center of a \(\pm 3\) dB interval. How you carry that interval into kilometers is your call to defend.
Note where LO works hardest — and where it doesn’t. The bands disagree, and that disagreement is the story.
Your five tasks#
Detection range vs aspect — \(R_{\max}(\theta)\) per class, in band. Justify your binning.
Uncertainty — propagate \(\pm 3\) dB of RCS into kilometers.
Visualization — one picture that tells the whole story.
Ingress implications — which class, which aspects, by how much. With numbers.
Recommendation — one slide to the mission planning cell.
Materials#
MATLAB · code/L9_Project1Starter.m↓
The starter skeleton handles the plumbing — it loads the CSV, converts dBsm to m², defines all three threat classes as a table, and computes one worked \(R_{\max}\) so you can verify your pipeline. Your analysis begins at the TODO blocks. Verify the worked number first. Then build. (The CSV is bundled inside the zip next to the starter, which reads it from the current folder.)
How to use the work day#
First 10 minutes — groups assigned, claim a whiteboard, read the handout together.
Next 30 minutes — divide the work: pipeline, uncertainty, visualization, story.
Last 10 minutes — regroup: what’s done, what’s blocked, who owns what before L10.
The instructor floats between groups — pitch your approach early. And plan the presentation first: it tells you what to compute.
Before you leave#
Pipeline verified against the skeleton’s worked number.
Task owners assigned through L10.
Questions for the instructor in writing tonight, not at 0700 before class.
Next lesson: L10 — Project 1 results presentations. Slides and code due before class, HW1 due at the start of class, and Quiz 1 in class.