Cell reception gets worse the further you get from cell towers in the outdoors. This makes it hard to respond in an emergency and use essential mapping services. As a result you are prone to getting lost or not able to call for help when it's needed.
We can use a secondary device to amplify the receiving and transmitting power of your phone. This lets you use the phone reliably at distances that would not be otherwise possible, keeping you connected when it's truly needed.
WHAT'S OUT THERE?
On the market there are plenty of signal boosters that allow you to extend your cellphone range, however, these are all either externally powered through a vehicle's battery supply or from AC power in homes. A portable booster would be able to compete with Iridium type cell phones which have been historically cost prohibitive for casual hikers. An integrated solar charger is not just possible but exceptionally useful for making sure your battery won't run dry in the bush.
These concepts were explored to fulfill the goal of boosting cell phone range, while being a standalone device that can keep your phone useable after any length of time off grid. This meant it had to generate and hold its own power and be used to charge a cellphone.
The design of the device changes in proportion dramatically based on different antenna types. The above concepts explore form factors for a directional antenna, a non directional antenna, and a patch antenna respectively. Each one offers their own benefit in form, power and reliability.
This flat antenna format was selected as it provides signal boosting with multiple output frequencies for different service providers. It boosts signals coming from multiple directions and, with a gain of 50dB, can reach cell towers up to 60km away. This antenna draws about 4 amps to boost at this rate.
It quickly became apparent after some interviews with people that this device should also be a secure place to store your phone when it isn't needed. Initial ideas to seal the phone in a waterproof bag would allow people to use their phone on the go, but were not be perceived as safe protection. This led to a rigid, waterproof case idea.
HIGH VISIBILITY, HIGH CONTRAST, DURABLE
The CMF choice of this product reflected the need for it to be visible, drop resistant and waterproof. Bright orange polycarbonate plastic is contrasted with black accents of the hinge and the ripstop nylon solar panel sheath.
BATTERY + BOOSTING
With a 10,000 mAh battery, this device is able to charge your cellphone 4-5 times over or provide 2.5 hours of continuous use of signal boosting.
Monocrystalline solar cells on the back side of the pack have a 5.5 Watt output, this can charge the booster between 7-8 hours depending on sunlight. A USB C connector inside the pack can charge at a rate of up to 3 hours depending on output.