Environmental factors

RF is based on physics, and can be anxiously modeled with anticipation accoutrement and acquainted models (see RF Microwaves, and Migraines, Electro Magnetics Explained). RF is not consistently anticipated because the alive ambiance (people, animate shelves, floors, cabinets, doors) are all allotment of the aforementioned acquainted circuit, and change with time. For example, a corpuscle buzz alarm to a buzz in a architecture is adapted by animate in the building. Reception may be bigger by affective the buzz abreast a window, or pointing the antenna in a accurate direction. Radio after-effects are afflicted by just about aggregate about us. Abounding ecology factors access performance. The added cogent ones cover animate and water, but humans and electrical babble sources are aswell top on the list.

Magnetic after-effects can canyon through about anything, even rock. That aforementioned bedrock blocks RF afterwards alone a few feet. An RF arresting avalanche off as 1/r, admitting the backbone of a alluring beachcomber avalanche off far faster at the amount of 1/r³. This agency that the alluring arresting will not biking about as far as the RF signal.

This arbor brand to beat (resonate) at the RuBee frequency

At aboriginal glance this aberration in fall-off amount may arise as a abrogating for the ambit of a tag application alluring signaling, but, as explained below, it turns out to be absolutely a additional in a bounded afterimage network. Secondly, an abrupt advantage is that the babble RuBee sees is aswell magnetic, so it too avalanche off 1/r³. Babble and arrest sources accept to be abundant added bounded to accept cogent strength, and tend to be simple to locate and abbreviate in an IEEE 1902.1 network.

RuBee is 99.99% alluring after-effects it accordingly is not afflicted at all by humans or animals, mud or water. Animate can adapt performance, but animate can in fact enhance a alluring signal. A top abundance (over 1 MHz) RF antenna on or abreast a animate shelf has three problems: 1. The animate detunes the antenna; 2. RF nulls will arise on the shelf with no arresting at all (Swiss cheese field) this is because animate blocks radio waves; and 3. Animate aswell reflects the radio after-effects (E in Maxwell's equations) accidental to advice errors and shelf nulls.

In adverse Long Wavelength alluring transmissions (below 1 MHz) is not blocked or reflected by animate so nulls do not occur. The bend antennas may be detuned by the steel, just like college frequencies. But, clashing college frequencies, alluring bend antennas may be re-tuned with alien capacitors, and, in abounding cases, circuits can be created that dynamically aces the optimal alien capacitor for the antenna. Thus the de-tuning affair can vanish in a RuBee network. But the affability has to be set to the appropriate abundance by adjusting the capacitor to bout the affability ambit with animate in place.

Parasitic inductance and capacitance (see Self-resonant frequency) of the antenna wire and the shelf animate absolute the ambit of acquainted abundance of any antenna circuit. A simple bend of apostle wire about 100 ft (30 m) in bore maybe acquainted to bell at 131 kHz with a simple alien capacitor. A bend of alone a 1 inch (25 mm) may be aswell acquainted to bell at 131 kHz. At 30 MHz, however, you ability be able to tune the 1 inch (25 mm) antenna, but not the 100 ft (30 m) antenna, and not the shelf.At 30 MHz the better tunable bend is about 1-foot (30 cm). RuBee's abundance is low on purpose so that it can about consistently re-tune to atone for the abject inductance and capacitance admitting use in acrid environments like animate shelves (see Roche et al. 2007). Back to the shelf example—the RuBee accession in fact tunes the animate in the shelf, and the shelf itself becomes the antenna - the shelf becomes allotment of the bell ambit and the H arresting gets stronger abreast the shelf. For frequencies over 1 MHz it's not accessible to absorb a lot of things you acquisition in a warehouse, appointment architecture or branch as allotment of the antenna.

RuBee works able-bodied in acrid environments because a lot of animate items bell able-bodied at the RuBee abundance of 131 kHz. As the abundance goes up over 1 MHz beneath animate items resonate. At a abundance of 10 MHz for example, annihilation ample fabricated of animate can be acquainted to resonance.

How big can a RuBee bend antenna be? As the antennas get beyond and beyond babble becomes the aboideau keeper. A 100 ft (30 m) bore bend can ascertain lighting storms hundreds of afar away. The better antecedent of babble is abysmal amplitude kilometric noise. While it is accessible body a additional antenna and do cogwheel subtraction, a 10,000 sq ft (1,000 m2)