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NTN & Direct-to-Device: 5G from Orbit — 5G certification courseWatch free

Free preview · Slant range, delay, Doppler and moving cells: what "high and fast" actually costs — opens in the course player

Intermediate

NTN & Direct-to-Device: 5G from Orbit

The satellite link taught as arithmetic, not architecture — slant range and delay you can compute, a link budget that closes in both directions, the pre-compensation a handset owes before it may transmit, and the mobility a moving cell forces on a network built for stationary ones.

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Lessons
27
Video
≈3.7h
Hands-on
10 exercises
Before you start
5G Foundation

About this course

Who it's for. RAN and core engineers, architects and technical leads evaluating or deploying non-terrestrial access.

Before you start. 5G Foundation. 5G RAN Specialist helps for modules 3 and 4 — timing advance, HARQ and handover are the terrestrial frames this course stretches.

This course includes

  • 27 video lessons — the first needs no account, and all are free for your first 7 days
  • 10 hands-on exercises — interactive labs and checkpoints
  • Study pack — question bank and slides
  • A free mock exam to find your gaps
  • Certification exam and a QR-verifiable certificate — with Prime Membership or this certification

Skills you'll gain

  • LEO, MEO & GEO geometry
  • Satellite link budgets
  • Transparent vs regenerative payloads
  • Doppler & timing pre-compensation
  • Random access over satellite
  • Moving cells & NTN handover
  • NB-IoT over NTN

Syllabus

5 modules · 27 lessons · certification exam

  1. Module 1 — From 'high and fast' to a number you can compute

    Turn “high and fast” into quantities: the three frames NTN stretches, and slant range and delay computed from an elevation angle.

    1. Slant range, delay, Doppler and moving cells: what "high and fast" actually costsWatch free7:06
    2. The standards lane and the product lane: one ladder, two railsFree with an account7:30
    3. Timing advance, HARQ and Doppler: the three frames this course stretchesFree with an account7:00
    4. Slant range from elevation angle: the first number you can computeFree with an account7:03
    5. High, or Fast? · Checkpoint~5 min
    6. How Far Is It Really? · Interactive lab~6 min

  2. Module 2 — Geometry, payloads and the budget that decides the service

    Weigh what an orbit buys and charges, place the gNB in a transparent or regenerative payload, and close a link budget in both directions.

    1. LEO, MEO and GEO: what altitude buys and what it chargesFree for 7 days with a free account, then with Prime Membership8:22
    2. Transparent and regenerative payloads: where the gNB sitsFree for 7 days with a free account, then with Prime Membership8:13
    3. EIRP, G/T and path loss: the downlink budget that closesFree for 7 days with a free account, then with Prime Membership8:43
    4. The uplink budget: why the handset is the weak endFree for 7 days with a free account, then with Prime Membership7:21
    5. From carrier-to-noise to service class: what the budget lets you promiseFree for 7 days with a free account, then with Prime Membership7:40
    6. Which Legs Did You Measure? · Checkpoint~6 min
    7. Which Direction Binds? · Interactive lab~7 min

  3. Module 3 — Making the radio work at 600 km

    Work out what a UE must hold before it may transmit, what it pre-compensates itself, and what breaks when timing advance and HARQ stretch.

    1. GNSS, ephemeris and epoch time: what a UE must hold before it may transmitFree for 7 days with a free account, then with Prime Membership8:14
    2. Doppler pre-compensation: the UE owns the service linkFree for 7 days with a free account, then with Prime Membership8:54
    3. Timing advance in four terms: open-loop pre-compensationFree for 7 days with a free account, then with Prime Membership8:34
    4. Random access over a satellite link: the first thing that breaksFree for 7 days with a free account, then with Prime Membership8:30
    5. HARQ and every closed loop at one round tripFree for 7 days with a free account, then with Prime Membership8:42
    6. Repetition and coverage: buying margin without feedbackFree for 7 days with a free account, then with Prime Membership8:14
    7. Who Supplies This? · Checkpoint~7 min
    8. Pick the Repair · Checkpoint~7 min

  4. Module 4 — Cells that move, and the network that follows them

    Hold the earth-fixed and earth-moving cell taxonomy exactly, and account for what a moving cell does to mobility, identity and signalling load.

    1. Earth-fixed, quasi-earth-fixed and earth-moving cellsFree for 7 days with a free account, then with Prime Membership7:50
    2. Service link switch, feeder link switchover and satellite switchFree for 7 days with a free account, then with Prime Membership8:17
    3. Conditional handover on distance and time: the NTN trigger eventsFree for 7 days with a free account, then with Prime Membership8:21
    4. NTN-to-TN handover: coverage broadcast, ephemeris on the ground, entry without random accessFree for 7 days with a free account, then with Prime Membership8:31
    5. Mapped Cell ID and core selection: a cell that crosses a borderFree for 7 days with a free account, then with Prime Membership7:40
    6. Regenerative operations: gNB on board and inter-satellite linksFree for 7 days with a free account, then with Prime Membership7:11
    7. What Does the Trace Show? · Checkpoint~6 min
    8. Judge the Claim · Checkpoint~6 min

  5. Module 5 — What is flying, what is specified, and what to track

    Separate the spectrum routes to orbit, size what one beam honestly carries, and read the release train for which capability is actually specified.

    1. MSS allocations and leased terrestrial spectrum: two routes to orbitFree for 7 days with a free account, then with Prime Membership8:10
    2. UE pre-compensation and payload compensation: who does the workFree for 7 days with a free account, then with Prime Membership8:44
    3. Per-beam capacity: what one footprint can actually carryFree for 7 days with a free account, then with Prime Membership8:57
    4. NB-IoT and eMTC over NTN: the standards-native business already shippingFree for 7 days with a free account, then with Prime Membership8:39
    5. PLMN selection, roaming and emergency routing: what an operator actually signsFree for 7 days with a free account, then with Prime Membership9:06
    6. Rel-17 to Rel-20: reading the NTN release trainFree for 7 days with a free account, then with Prime Membership8:46
    7. One Beam, Everybody Under It · Interactive lab~6 min
    8. Which Track Owns It? · Checkpoint~6 min

  6. Certification exam

    Earns a certificate

    35 questions · 60 min · 65% to pass — earns your TELCOMA Certified NTN Specialist, a QR-verifiable certificate.

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Not ready yet? Take a free 20-question mock exam first.

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Certification

Earn the TELCOMA Certified NTN Specialist

Pass the 35-question exam with 65% or more, and the certificate is yours to show anyone.

  • Show proofEvery certificate carries a QR code and a public page that anyone can check.
  • Add it to LinkedInPut it in the Licenses & certifications section of your profile in one click.
  • Build a collectionEach of our 13 courses earns its own certificate.
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Every lesson free for 7 days, no card. The exam comes with Prime Membership or this certification.

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Specimen of the TELCOMA Certified NTN Specialist certificate — the real design, marked SPECIMEN
The certificate you receive — shown as a specimen.

Study materials

Free for 7 days

Download the NTN & Direct-to-Device: 5G from Orbit question bank and slide deck — every signal check in the course, with answers, plus every figure.

  • Question BankPDF37 KB
  • Slide DeckPPTX15 MB
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Free with a new account for your first 7 days — no card. After that, the question bank and slides come with Prime Membership or this certification.

Hands-on learning

Do it, don't just watch it

Modules end with a hands-on exercise — 10 in this course. You move the controls, the numbers answer back, and a wrong turn tells you why.

Try this one first:

How Far Is It Really? · Interactive lab · ~6 min

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Free with an account — no card.

How Far Is It Really? — a hands-on interactive lab from NTN & Direct-to-Device: 5G from Orbit

What you'll build

3 of 10 — the rest are in the syllabus

Ways to learn

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  • Lessons and labs in this course
  • Study pack — question bank and slides
  • Certification exams and verifiable certificates — 1, for this course
  • Every other course — first module
  • Not included: Full-length practice exams
  • Not included: TelcoMentor AI coach
  • Hands-on scenarios — traces, logs, configs — selected traces

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Every course for your first 7 days, then the first module of each

  • Lessons and labs in this course — all for your first 7 days, then the first module
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  • Not included: Certification exams and verifiable certificates
  • Every other course — all for your first 7 days, then the first module
  • Full-length practice exams — for your first 7 days
  • TelcoMentor AI coach — for your first 7 days, at a smaller daily limit
  • Hands-on scenarios — traces, logs, configs — all for your first 7 days, then selected traces
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