12 The specifications this work created, and the ones it changes

12.1 Why a list like this is the part people come back for

The chapters before this one are arranged by who did the work, which is how it happened but not how anybody reads afterwards.

Afterwards you arrive with a question. What must a satellite base station transmit. What does a phone have to prove before it is allowed on. What changed in the 5G architecture. You want the one document that answers it.

This register holds 102 specifications, against 3599 active 3GPP specifications altogether ^{[9] [10]}.

A further 149 documents are named by fewer satellite documents than the register's own rule keeps ^[11].

The 102 fall into two piles, and the piles behave completely differently. One half did not exist before this work. The other half existed already and had satellite text cut into it.

12.2 What did not exist before

12.2.1 The satellite access node, and the thing that tests it

A satellite access node is the base station of this world: the payload in orbit plus the equipment on the ground, taken together. Two documents describe it.

TS 38.108 is what it has to transmit and receive TS 38.108. It carries 465 satellite documents, 387 of them change requests. Its scope is one sentence:

Two things in that sentence are easy to walk past. It covers the newer radio and the older internet-of-things radio in the same document, and it is about in-band operation — a satellite access node sharing a band rather than one living alone.

TS 38.181 is how you prove a node meets it TS 38.181. 374 satellite documents, 220 of them change requests, and its scope names the three shapes of node it tests:

12.2.2 The device side, which took more work than the node

TS 38.101-5 is what a phone has to do to use satellite access TS 38.101-5. It carries 838 satellite documents and 771 change requests, which makes it the second most worked-on document in this register.

TS 38.521-5 is its conformance half, with 371 satellite documents against it TS 38.521-5:

The device side being heavier than the node side is not a surprise once you see it. There are more device makers than satellite operators, every band is a new row of requirements, and every requirement has to be turned into a test.

12.2.3 The same four documents again, on the older radio

The internet-of-things side of this subject runs on the older LTE radio, and it got its own four documents rather than a section in the NR ones.

Document	What it is	Satellite documents	Change requests
TS 36.108 TS 36.108	the satellite access node	176	156
TS 36.181 TS 36.181	its conformance tests	123	90
TS 36.102 TS 36.102	the device	376	337
TS 36.521-4 TS 36.521-4	the device's conformance tests	291	136

The same imbalance shows up here: on both radios, the device documents carry more than the node documents do.

TS 36.102's scope is the shortest of the eight:

12.2.4 The one that holds the radio-frequency argument

TR 38.863 is where the radio-frequency and coexistence work for this whole subject lives, and it says of itself exactly which work item it belongs to TR 38.863:

238 satellite documents, 133 of them change requests. Every NR band work item in this subject names it, which is where most of that traffic comes from.

12.2.5 The study reports the whole subject rests on

A study report is homework, not a rule. Nobody has to obey one. But every rule in this subject was argued out in one of these first, and they are the shortest route to what a phase was actually about.

Report	What it studied	Satellite documents
TR 38.811 TR 38.811	the first look at NR over satellite	90
TR 38.821 TR 38.821	solutions for it	265
TR 36.763 TR 36.763	the same on the internet-of-things radio	25
TR 22.822 TR 22.822	using satellite access in 5G at all	86
TR 22.865 TR 22.865	requirements, phase 3	176
TR 22.887 TR 22.887	requirements, phase 4	269
TR 23.737 TR 23.737	the first architecture	305
TR 23.700-28 TR 23.700-28	architecture, phase 2	170
TR 23.700-29 TR 23.700-29	architecture, phase 3	391
TR 23.700-19 TR 23.700-19	architecture, phase 4	485
TR 23.700-27 TR 23.700-27	satellite backhaul	98
TR 24.821 TR 24.821	which network to choose from orbit	213

Two of those carry a warning that matters more than their numbers. TR 38.811 and TR 38.821 are the two studies the whole radio line stands on, and there is no parsed text of either on this machine TR 38.811 TR 38.821. They can be named here and counted here and never quoted here.

Fourteen of the 102 are in that state altogether, TR 22.822, TR 23.700-27, TR 23.700-28, TR 23.737, TR 24.821 and TR 28.808 among them.

The architecture reports that can be quoted say their first aim outright. TR 23.700-19's is a voice call over the narrowband internet-of-things radio through a geostationary satellite, into the older packet core ^[12].

TR 23.700-29's first aim was the regenerative payload architecture, where part of the base station is in orbit ^[13].

12.2.6 Two more that this work created and almost nobody cites

TR 37.911 is 3GPP checking its own satellite radio against the international requirements TR 37.911. Its scope says only that it reports self-evaluation results against a requirement set defined elsewhere:

17 satellite documents name it, while the work item behind it, FS_IMT2020_SAT_eval, carries 179 FS_IMT2020_SAT_eval. Those two numbers count different things, and the report itself is the thinner of them.

TR 38.882 is stranger still. It is a Release 18 study on requirements for a network-checked device location, and no document in this subject names it at all TR 38.882 FS_NR_NTN_netw_verif_UE_loc. It is in the register because a work item created it, and for no other reason.

Both are worth knowing about for the same reason: a document existing is not evidence that anybody built on it.

12.2.7 The band reports, and the one about losing your position fix

Three more reports were created by this work and none of them is about the system at all. They are about spectrum and about one specific failure.

• TR 38.741 TR 38.741 holds the L and S band work for NR, and says of itself only that it is a technical report for that work item. 62 satellite documents.

• TR 36.764 TR 36.764 does the same for the internet-of-things bands on the older radio. 31 satellite documents.

• TR 38.742 TR 38.742 is the Release 20 study of what happens when the satellite navigation fix goes away. 10 satellite documents so far.

That last one is worth quoting, because it is the clearest statement in the register of a dependency this whole subject carries:

12.3 What was already there, and took the hardest editing

The other half of the shelf is documents that existed long before anybody put a base station in orbit. This is where the real cost of the subject shows.

A change request is the only way one of these is ever altered. It names the document, the version, the clause and the exact words, and it is argued over one at a time.

So the count of change requests against a document is a count of the separate arguments that were had about it.

The counts below are counts of documents in this record that carry a satellite work item short name and name that specification. They are not counts of everything ever written about the document, and they are floors for the same reason every count in this course is.

12.3.1 The heaviest of them all

TS 38.133 holds the radio resource management requirements: how long a device may take to find a cell, measure it, report it and move to it TS 38.133. It carries 1426 satellite documents, 1306 of them change requests — more than any other document in this register.

Why that document above all others, the register does not say. What it records is the scale: no other specification in it was changed as heavily by this subject, and the work items doing the changing are the radio ones.

Its LTE twin, TS 36.133, carries 377 satellite documents, every one a change request TS 36.133.

12.3.2 What a device says to the network

TS 24.301 and TS 24.501 are the protocol a device speaks to the core, in the older and the newer system: 705 and 560 satellite documents TS 24.301 TS 24.501.

The phase 3 architecture work item's own table says what it wanted out of TS 24.301 — updates to the signalling procedures for store-and-forward operation, where a satellite collects a message now and delivers it when it next has a path 5GSAT_Ph3_ARCH.

12.3.3 The 5G system itself, and the one before it

TS 23.501 is the model of the 5G system and TS 23.502 its procedures: 486 and 214 satellite documents TS 23.501 TS 23.502. Five work items name TS 23.501 in their own table of what they change and seven name TS 23.502, from the first architecture phase through to phase 4 and backhaul.

TS 23.401, the older packet core, carries 570 TS 23.401, and four of these work items name it. It is easy to overlook. The internet-of-things satellite work lives in the older core rather than the 5G one, and so does the geostationary voice call phase 4 is chasing.

12.3.4 The radio's own control and description documents

TS 38.331 and TS 36.331 are the radio control protocol of each radio — what a base station tells a device about the cell and how the device answers: 589 and 357 satellite documents TS 38.331 TS 36.331.

TS 38.300 and TS 36.300 are the overall description of each radio network, the document somebody reads first: 471 and 300 TS 38.300 TS 36.300.

12.3.5 The network interfaces, the policy rules and the warning messages

Three more existing documents are worth naming because they are where satellite work reaches parts of the system nobody expects.

• TS 38.413 TS 38.413 is the protocol between the radio network and the 5G core, and TS 38.423 TS 38.423 the one between two radio network nodes: 152 and 66 satellite documents. Both belong to RAN3.

• TS 23.503 TS 23.503 holds the policy and charging control rules of the 5G system: 69 satellite documents. The phase 4 architecture work item names it in its own table 5GSAT_Ph4-ARC.

• TS 23.041 TS 23.041 is how a public warning message is broadcast to every phone in an area: 45 satellite documents. A whole Release 19 work item, PWS_NTN, exists to make that work over satellite radio PWS_NTN.

That last one is the clearest illustration of what "an existing document got changed" means in practice. A warning to everybody in an area assumes the network knows what the area is. Deliver the same message from orbit and that assumption needs writing down again.

12.3.6 Where the requirements land

TS 22.261 is the 5G service requirements document, and it is where every SA1 result in this subject ends up: 122 satellite documents TS 22.261. Five of these work items name it in their own change table.

It is a small number for an important place. Requirements text is short; the argument that produced it is not.

12.3.7 The conformance shelf, which is RAN5's

Testing has its own pile, and it is larger than most people expect.

Document	What it is	Satellite documents
TS 38.533 TS 38.533	device tests for radio resource management	299
TS 38.523-1 TS 38.523-1	5G device protocol conformance	213
TS 36.523-1 TS 36.523-1	the same on the older radio	183
TS 36.508 TS 36.508	the common test environment, older radio	145
TS 38.508-1 TS 38.508-1	the common test environment, 5G	118
TR 38.903 TR 38.903	how test tolerances are derived	79

12.3.8 Management and charging

Two more, both SA5's, and both covered in Security, the bills, the management, the layer above and the voice: TS 28.541, the network resource model, with 88 satellite documents TS 28.541, and TS 32.255, the 5G data charging specification, with 40 TS 32.255.

12.4 Which document answers which question

The two halves above are arranged by what happened to each document. Most people arrive with a question instead, so here is the same shelf arranged that way.

Your question	The document
What must the system be able to do?	TS 22.261 TS 22.261
What is still being argued about?	TR 22.887 TR 22.887
Can the radio do this at all?	TR 38.811 then TR 38.821 TR 38.811 TR 38.821
What must a satellite base station transmit?	TS 38.108 TS 38.108
What must a phone do?	TS 38.101-5 TS 38.101-5
How is either of those proved?	TS 38.181 and TS 38.521-5 TS 38.181 TS 38.521-5
What about interference and coexistence?	TR 38.863 TR 38.863
How is the system put together?	TR 23.737, then the phase reports TR 23.737
What changed in 5G itself?	TS 23.501 and TS 23.502 TS 23.501 TS 23.502
What changed in the older core?	TS 23.401 TS 23.401
What does a device say to the network?	TS 24.501, or TS 24.301 for the older core TS 24.501 TS 24.301
What did the timing requirements cost?	TS 38.133 TS 38.133
What about sensors and trackers?	TR 36.763, then TS 36.108 TR 36.763 TS 36.108
Is it secure?	TR 33.700-29 and TR 33.700-30 TR 33.700-29 TR 33.700-30

Two of those rows will disappoint anybody who follows them. The radio row points at two study reports whose text is not on this machine, so this school can name them and never quote them.

The security row points at two studies rather than at a satellite security specification, because there is no such document — the security result went into TS 33.401 TS 33.401.

12.5 What "in the register" means, and what it leaves out

A specification is in these 102 when enough satellite documents name it, or when a work item's own table says it will be changed. Three consequences follow and a careful reader should know all three.

• 149 more specifications are named too thinly to keep ^[11]. One or two mentions is as likely a filing slip as a real link, and a register that guesses is worse than one that abstains.

• Two documents whose own titles say satellite or NTN are not here at all — TR 38.763 and TR 38.908 — because no document and no work item of this subject points at either.

• Six entries in the work plan's own list of documents these work items change gave no readable specification number. Those documents are not in the register and cannot be named here.

12.6 Where to read the real thing, in order

This school carries the text of none of these. A reading order that works, for somebody who has to use the subject rather than admire it:

• R1. TS 22.261 TS 22.261 for what the system is required to do, and TR 22.887 TR 22.887 for what phase 4 is still arguing about.

• R2. TR 38.811 then TR 38.821 TR 38.811 TR 38.821 for the radio, in that order — the second answers the first.

• R3. TS 38.108 TS 38.108 for what a satellite base station has to be, and TS 38.101-5 TS 38.101-5 for what a phone has to be.

• R4. TR 23.737 TR 23.737 and then the phase reports in order: TR 23.700-28, TR 23.700-29, TR 23.700-19 TR 23.700-28 TR 23.700-29 TR 23.700-19.

• R5. TR 36.763 TR 36.763 for the internet-of-things side.

How far each of these has got, and what the pile of paperwork behind them says, is What the shape of the paperwork says, and where the work stands.