Results and the survey grade
When you stop a survey with at least three cubes, ARRF opens the Results screen (also reopenable from any History row). It leads with a plain-language verdict, grades the walk, summarises it, and flags the weak spots.
What the Results screen shows
Section titled “What the Results screen shows”From top to bottom:
- 3D survey — when the walk captured a LiDAR surface, the 3D survey leads the screen, slowly turning; tap it to explore full screen.
- Grade card — an editable survey title, the date and cube count, then the verdict: one plain-language headline such as “The Wi-Fi is the weak link, not the internet.” with a supporting sentence. The letter grade sits beside it only when show letter grade is on (see below).
- On a survey with AP-side signal (the RUCKUS pack), the card also carries the connection-health score out of 100, a stat row (median dBm, coverage %, metres walked, roams), a grade breakdown, and a “How this was measured” scope note.
- On a phone-measured survey (Any Wi-Fi), the card carries the experience grade and its breakdown instead.
- Experience card — on a RUCKUS survey that also measured experience, the experience grade in its own card.
- Voice and Network policy cards — the simulated-call results and the internet policy check, when measured. See What the phone measures.
- Rooms — per-room ratings, when you tagged rooms. See Rooms and sites.
- Floor plan — the LiDAR reconstruction, if one was captured.
- Walk map — a top-down minimap you can shade by metric.
- On a RUCKUS survey: Signal histogram, band shares, a roam card, an AP-share card, and a weakest-spots card.
- On an Any Wi-Fi survey: a Roaming card of roams seen by the phone, and an access-point share card.
- On the demo: a What a real survey tells you card with a Survey my Wi-Fi button.
Why is there no letter grade?
Section titled “Why is there no letter grade?”The letter shows only when show letter grade is on. It follows the Home or Professional? answer: Home (also the default before you answer) hides the letter so the verdict leads alone; Professional shows it. You can change it in Settings.
How is the verdict chosen?
Section titled “How is the verdict chosen?”The verdict is a fixed sentence picked from the experience Wi-Fi and internet subscores and the RF grade — no AI, so the same survey always reads the same way. A part that wasn’t measured is never called good. The full list of headlines is on The experience grade.
What the RF grade measures
Section titled “What the RF grade measures”The RF grade applies when the RUCKUS vendor pack supplied AP-side signal. ARRF grades connection health, not area coverage. Every signal value is read from the serving AP over SSH — how the AP hears this phone (the uplink direction). iOS exposes no downlink RSSI and no passive multi-AP scan to third-party apps, so the grade is honest about scope: it scores one device’s connection health and roaming as you walked. Uplink is the conservative direction.
How the score is calculated
Section titled “How the score is calculated”Each sample is scored against a requirement you set (and that is captured into every export), with these defaults following common WLAN design convention:
| Target | Default | Meaning |
|---|---|---|
| Primary | −67 dBm | Full credit at or above this signal |
| Edge | −72 dBm | Zero credit at or below; credit fades linearly between edge and primary |
| Min SNR | 25 dB | Full credit at or above; credit fades linearly to zero 10 dB below it (so 15 dB scores zero at the default) |
The scoring is continuous — no hard band cliffs — and it deliberately can’t average away a dead spot:
- Each sample gets a 0–1 signal quality and a 0–1 SNR quality.
- Each sub-score blends the mean 50/50 with the worst-decile (10th-percentile) sample — a worst-decile gate, so weak spots pull the score down.
- The two sub-scores combine 60% signal + 40% SNR, minus 8 points per flagged roam, counting at most 3 — so the roam penalty is capped at 24 points and a survey cannot fail on roams alone.
- The result is clamped to 0–100.
A very long survey still grades the whole walk. Past 20,000 placed readings (roughly two hours of continuous capture) ARRF thins the set by keeping every other reading, newest always kept, so spatial coverage stays roughly even and nothing is cut off; the worst-decile gate still finds the weak spots. See Long walks and hot phones.
Both sub-scores are shown on the Results screen next to the letter, along with the percentage of samples meeting each target and the flagged-roam count, so the grade is always decomposable.
The final 0–100 score maps to letters:
| Grade | Score |
|---|---|
| A | ≥ 90 |
| B | ≥ 75 |
| C | ≥ 55 |
| D | ≥ 35 |
| F | below 35 |
| N/A | fewer than 10 readings — too few to grade, not an F |
A survey with fewer than 10 readings is N/A, not F; F is reserved for a genuinely-scored floor. The experience grade uses the same letters and the same 10-cube minimum.
Weak spots
Section titled “Weak spots”The worst-decile effective dBm is the weak-spot indicator, and the in-app weakest-spots card keeps the three weakest samples (weakest first), ringed on the walk map. The PDF report keeps up to ten.
Flagged roams
Section titled “Flagged roams”ARRF flags two kinds of problem handoff, and one roam can carry both:
- Weaker signal — handed off to a weaker signal (SNR dropped 3 dB or more).
- Ping-pong — bounced straight back to the AP it just left within 30 seconds.
The flagged-roam count drives the roam penalty in the grade and appears in the breakdown and the reports. Roams seen by the phone on an Any Wi-Fi walk are covered in AP locations and roaming.
Adjust the requirement
Section titled “Adjust the requirement”The primary/edge/SNR targets live in Settings → Grade requirement. Because they’re captured into each export, a report always states — and grades against — the requirement that was set when it was captured.
Changing the targets does not re-grade surveys you already saved: each one keeps the requirement it was captured with, which is why an old report and a new one can disagree about the same floor.