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In Its First Public Acquisition, SpaceX Snatches Up Satellite Startup Swarm

August 12, 2021 by Adrian Gibbons

SpaceX is known to create almost all of its technology in-house. What inspired the tech giant to acquire Swarm's technology?

This week, SpaceX entered into an acquisition phase with Swam Technology, a startup said to provide novel narrowband low-cost connectivity via a satellite network.

Swarm owns a network of small-scale satellites along with the technology required to communicate with that network. On July 16th, 2021, Swarm’s CEO, Sara Spangelo, entered into a merger agreement with SpaceX to become a subsidiary company under the SpaceX banner. 

Its flagship commercial product, the Swarm Tile, is one key technology that may have driven the upcoming merger. Beyond its technology, the acquisition grants SpaceX radio and satellite licenses in the 137–138 MHz and 148–150.05 MHz ranges.

 

The Swarm Tile module

The Swarm Tile module (shown shielded with U.FL connectors exposed). Image used courtesy of Swarm

 

Following the agreement, SpaceX has officially petitioned the FCC for a transfer of license for the radio frequency bands assigned to Swarm and its associated 150 satellite licenses.

 

Introducing the Swarm Tile SMT Module

The Swarm Tile is a PCB surface-mount technology modem, which is capable of uplink and downlink connectivity with the Swarm constellation of satellites. It can be used in a variety of applications including services for maritime, agriculture, transport logistics, and remote data access. Its data is AES-256 encrypted and available for routing through a cloud server using REST API.

 

Depiction of Swarm's network architecture

Depiction of Swarm's network architecture. Image used courtesy of Swarm
 

The module, which operates at 3.3 V, is designed to be mounted directly to a PCB in custom applications and can communicate directly with a host device over a 3.3 V CMOS UART interface or indirectly with a USB serial converter IC.

 

The Swarm Tile

The Swarm Tile (left of PCB) has been integrated with a reference power design. Image used courtesy of Swarm

 

The system downlink, operating in the 137–138 MHz range, consumes ~100 mW under typical conditions. Meanwhile, the maximum output power of the transmitter, an uplink in the 148–150 MHz range, requires just under 3.3 W.

The overall system throughput is 1 kbps with a maximum packet size of 192 bytes. Its communications systems include a VHF radio and a GPS receiver. The module measures 58.7 mm x 27.4 mm x 6.0 mm and weighs in at 14 g. 

As a radio device, the Swarm Tile is susceptible to receiver interference, and Swarm has addressed this issue by providing detailed design documentation to help reduce time to market.

 

Design Consideration for Using the Swarm Tile

Power supply noise can easily destroy the signal coherence of a radio receiver and must be treated as a critical design component in any radio system. Quieting the SMPS requires several stages of feedthrough capacitors, filters, and shielding.

Designers have access to several reference designs, including a low-noise DC-to-DC converter for the Swarm Tile. Additionally, Swarm has provided guidance on navigating end-product system-level FCC certification.

 

Block diagram of the reference DC-DC converter for the Swarm Tile

Block diagram of the reference DC-DC converter for the Swarm Tile. Image used courtesy of Swarm

 

The reference buck-only low-noise PSU from Swarm is said to have spurious noise levels below -113 dBV in the operational range of the Swarm Tile. The input voltage for this design can range from 3.8 V to 28 V with an output of 3.3 V at 1.5 A max. 

Swarm’s technology and satellite network are certainly interesting and provide real value to industrial IoT applications. But why exactly did Swarm catch the eye of SpaceX?

 

Why Is the SpaceX Acquisition Important?

Until there is an official announcement regarding this merger, the industry can only wonder about the benefits that Swarm brings to SpaceX. Examining the FCC’s transfer of control document reveals that SpaceX could become the owner of several important radio licenses, both terrestrial and in orbit.

 

List of licenses currently under review for transfer to SpaceX

List of licenses currently under review for transfer to SpaceX. Image used courtesy of the FCC

 

As an additional benefit, Swarm appears to be already commercially viable. The Swarm service uses a subscription model claimed to enable low-cost connectivity worldwide. 

It's likely that SpaceX could be looking to acquire this potentially lucrative satellite network and add it to its existing Starlink portfolio. For now, we will have to await a more formal release detailing the Swarm-SpaceX merger.