A single consignment crosses cellular, open ocean and airfreight on one journey. Item-level custody has to survive every gap between them — which means the tracker cannot assume a network is there to report to.
High-value goods in distributed logistics do not move through one network. A consignment leaves a depot on cellular, climbs a mountain road where coverage is intermittent, sits on a ship for days with no terrestrial network at all, is transhipped and flown, then arrives somewhere with cellular again. Each leg has a different answer to the question “can the device phone home right now?”
Container-level tracking is not enough here. The value, and the shrinkage, are at item level — individual cartons and packages, hundreds per consignment — and each handover between infrastructure owners is a moment where custody can be lost or disputed. So the requirement is item-level custody that holds continuously, not a position that reappears at the next port.
Which produces the real problem. A device that depends on a network being present goes dark for the most important legs of the journey — exactly where goods are hardest to recover and easiest to divert. The tracking has to degrade gracefully to satellite and to store-and-forward, and it has to do it on a battery that lasts the whole transit.
Stated as the operator stated them, before any of them had an answer. A challenge described only after it was solved is a description of the solution.
Mid-ocean and across mountain corridors there is no ground cell to find. The device has to recognise that, fall back to satellite NTN, and hold custody in store-and-forward until a link returns — without flattening the battery searching for a network that is not there.
Hundreds of items per consignment cannot each carry a cellular-plus-satellite modem, on cost or on power. The architecture has to be a mesh of inexpensive item tags under a parent that holds the expensive radios.
A sea leg is measured in weeks. The whole energy budget — sensing, mesh, and the satellite transmits that dominate it — has to fit a battery that is not recharged until the goods arrive.
A position log that can be edited proves nothing in a dispute. Identity and integrity have to be rooted in the device, so a record can be trusted regardless of which network carried it.
One multi-mode part at the parent — the ALT1350 — carries cellular, satellite NTN, the sub-GHz item mesh, GNSS and a secure element. The items themselves stay cheap and low-power on the mesh; only the parent decides when a leg has gone out of coverage and when a satellite pass is worth the energy.
The specific scope, rather than a capability list. Where a stage was shared with the customer’s team, it is described as shared.
Rarely the subsystem that sounds difficult. Written out because a reader facing the same programme gets more from this than from a summary of what went well.
The expensive mistake is hunting for a terrestrial cell that is not there. Bearer arbitration — how long to try cellular, when to commit to a satellite pass, when to simply store and wait — is where most of the battery is won or lost, and it took the most tuning against real journeys.
Cellular, satellite NTN, sub-GHz 802.15.4 and GNSS coexisting on a small tracker without one blinding another is an RF and layout problem, not a software one. It was settled early because it constrained the mechanics.
Extended sleep, message batching and reporting on exception are the levers; the satellite transmit is the event that dominates the budget. Getting a whole-voyage figure that survived cold, motion and duty-cycle reality took measurement, not datasheet arithmetic.
Custody is only worth logging if it cannot be quietly rewritten. Anchoring identity and signing in the ALT1350’s secure element and iSIM — rather than trusting whichever network carried the message — is what makes the ledger evidence rather than a claim.
Item-level custody continuous across depot, mountain, ocean and air — satellite and store-and-forward filling every gap where terrestrial cellular is absent.
The ALT1350 replaced separate cellular, satellite, mesh and secure modules, shrinking the parent’s bill of materials, board area and power at once.
Duty-cycled sensing, mesh and satellite reporting sized so the parent survives a multi-week transit on the specified cell, using the part’s roughly four-times battery advantage.
Signed on the device through the secure element and iSIM, so a position and hand-over record is defensible rather than merely stored.
Customer projects are presented at property, capability, outcome and integration level. Customer names, internal architecture, bills of materials, firmware and confidential deliverables are not disclosed. Named silicon refers to a commercially available third-party component, not to any customer. More detail is available under a non-disclosure agreement, within the limits each customer has agreed.
Every item links to its own page, with characteristics, applications and maturity stated honestly for that item.
The satellite-capable tracker.
PRODUCTThe terrestrial baseline.
PRODUCTSBLE, cellular, NTN, NFC, UWB and RFID.
CAPABILITYMulti-radio front ends and antenna.
CAPABILITYThe low-power parent board.
CAPABILITYThe custody ledger and fleet.
NTN is non-terrestrial network connectivity — the satellite complement to cellular, standardised so a device can reach a satellite when no ground cell is in range. Consignments spend days with no terrestrial coverage: mid-ocean, over mountains, in the air. Without a satellite fallback, custody goes dark for those legs and only reappears at the next port or hub.
No — the economics and the power budget do not allow it. Items carry low-cost tags that form a short-range sub-GHz mesh under a parent tracker; only the parent holds the cellular and satellite radios and backhauls the aggregated custody record for the whole consignment.
By treating the satellite transmit as the expensive event and everything else as cheap. Extended sleep, message batching and reporting on exception rather than on a fixed cadence keep the average current low. The ALT1350 is specified for roughly four times the battery life of the previous generation for a typical device, which is what makes a whole-journey budget realistic.
Identity and signing are rooted in the device rather than trusted to the backhaul. The ALT1350 carries a secure element and an integrated SIM, so each position and custody event can be signed on the device and verified downstream — an edited log becomes detectable rather than plausible.
Because it collapses the bill of materials for exactly this problem into one ultra-low-power part: LTE-M and NB-IoT for terrestrial cellular, satellite NTN for the out-of-coverage legs, an integrated sub-GHz and 2.4 GHz 802.15.4 transceiver for the item mesh, concurrent GNSS for position, an on-chip MCU and sensor hub, and a secure element with iSIM. One device does the job that used to take separate cellular, satellite, mesh and secure modules.
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