Get IT Done - IT Comes From Space

Last month we discussed how the electromagnetic (EM) spectrum powers computing devices. This month we discuss how computing devices use EM waves to communicate.

Like the gas molecules in our atmosphere, EM waves wash over us constantly. But, unlike gasses, the gravity of Earth does not hold down these self-propagating and massless waves of energy. The EM waves we produce propagate out from our planet at the speed of light (186,000 miles/second) and we have been generating EM waves for long enough to have advertised our existence to anyone within a radius of about 60 light years (over 352 trillion miles). While that is amazingly far, the universe is astoundingly vast at 13 billion light years.

As we push EM waves into space, space reciprocates by bombarding the Earth with EM waves. While most of the EM waves we receive come from the Sun, we also receive EM waves from other stars and Cosmic Microwave Background (CMB) radiation. CMB is the name for residual EM waves from the Big Bang, the origin of the universe’s expansion.

Interestingly, these waves were discovered serendipitously. In 1964, while Arno Penzias and Robert Wilson, Bell Labs physicists, were trying to map radio signals from the Milky Way, they were continually frustrated by a background hiss in the signal. Thinking that the noise was generated by a physical imperfection in their dish antenna they sealed all gaps and taped over the bolts, but the noise persisted. They found pigeons on the dish and, considering that their droppings may have caused the issue, they removed the birds and cleaned the poo. Yet the noise persisted. This noise was determined to be radiation remaining from the Big Bang. Labeled CMB radiation, it has reverberated throughout the universe for billions of years. Fascinatingly, if you set a TV or radio tuner between stations, about 5% of the static you see or hear may be from CMB.

But how do these electro-magnetic waves support our computing environment? While there are many uses for EM waves in computing, it is most leveraged as a vehicle for wireless communication. EM waves are characterized by the frequencies on which they operate, and the type most often used in computing devices (or communication in general) are radio waves. WiFi, wireless Ethernet, Bluetooth, and an assortment of other computing protocols use radio waves to connect without wires. While using unique frequencies, computers use EM waves in a comparable manner to walkie talkies, car radios, cell phones, and weather radios.

Radio waves will penetrate most material, but brick, mortar and steel structures may absorb or reflect the waves. If you are experiencing wireless challenges, you may need to move the transmitter/router to preclude the structure you are in from defeating your communication.

Years ago, my firm created wireless metropolitan area networks, and I was surprised to discover that in addition to brick and steel structures, new windows were a big suppressor of EM waves. These windowpanes are designed to filter EM waves to prevent the Sun’s rays from beaching furniture and carpets. In these homes we found it necessary to install external antennas on the outside of the buildings to guide the signal around the brick, mortar, and EM suppressing glass.

get IT done Remember that your computers and mobile phone uses radio waves. If you are having problems with coverage in an area it may not be the vendors signal strength that is problematic, but the structure you are in. You may also experience interference from EM waves around you including those from space.

EM waves are everywhere and form a framework for our civilization. Connect wirelessly and…

Think About IT!

Tony Keefe, COO, Entre Computer Services www.entrecs.com