Introduction
Cell phones are an indispensable tool of modern life with more than two billion cellular subscribers worldwide. Cell phone service, however, is often lacking and the number one reason people switch service providers -- only to discover service issues plague all providers. People expect good cell phone service where they use their cell phone the most, which often is in locations where the cellular service providers fail to deliver reliable service. Cellular providers deliver inadequate service for two primary reasons: 1) too little, or ‘weak’ serving signal, and 2) interference. Weak serving signal is easier to understand; it is comparable to using a cordless telephone and walking too far away from the base station (unit that plugs into the phone line) and losing the connection. Interference is similar to a crowd of people where everyone is yelling to try to talk with each other, yet few can understand what’s being said. In this paper, these two service issues will be addressed together unless otherwise specified. Other less common reasons for poor cellular service include equipment failure, poor system maintenance, intermittent network connections between cell sites and central office, and low cost/low performance equipment.
The CelLynx Repeater
The CelLynx repeater is a plug and play, consumer focused device designed to be easy to use and understand. Like all repeaters, the CelLynx repeater boosts cell phone signals to combat the primary cell phone service issues; coverage and interference. Unlike other repeaters, the CelLynx repeater is a single unit containing the antennas and the active stages needed to get the job done.
The CelLynx Advantage
CelLynx set out to create a breakthrough solution for in-home cell phone service enhancement that would be plug and play, reliable and high performance. CelLynx engineers tackled these requirements with advanced technology that is applied in the high performance base stations for the new and future wireless systems called 3G and 4G wireless networks.
Reliability and high performance is ensured by leveraging technology developed for wireless systems. Plug and play demands complex algorithms and intuitive interfaces that provide all the interworking elements needed for the best performance in all conditions. CelLynx has met the challenge, and its repeater is expected to perform flawlessly over time under varying conditions.
Plug and play demands complex algorithms and intuitive interfaces that provide all the interworking elements of a highly advanced, world class repeater.
Typical Performance of a CelLynx Repeater
It’s All in the Bars
The signal strength bar indicator on cell phones has been used by some wireless service providers as a marketing ploy for years. Ever notice a poor service area with many bars indicated? Interference is the primary cause of poor service in areas where the bars on the phone indicate good coverage. The CelLynx repeater will almost always remedy the service problem by directing a boosted signal between the cell phone and serving cell site to overcome the interference. By using a directional donor antenna, the interfering signals are reduced at the same time that the desired signals are increased.
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A repeater simply boosts the off the air cellular phone signals, so operating performance of a repeater can be related to the amount of boost it delivers reliably. System gain is the measure of boost in decibels or dB. The major obstacles to reliable gain in a repeater are isolation and linearity. Linearity is a function of the amplification in the active portion of the repeater. Typically, the amplifiers in a repeater are designed to operate class A and the usable output power is de-rated from the maximum output power by 10dB or 90% below the saturated output power of the amplifier. Isolation is the measure of separation of the input from the output of the repeater and is important because if the separation is less than the system gain, it can lead to a feedback screech similar to that heard when a microphone is placed too close to a loud speaker. In practice, isolation has proven to be the Achilles heel of repeaters because unlike linearity, improvements in isolation have proven to be costly or unmanageable for an affordable consumer device. Traditional low tech approaches to achieving the isolation necessary for adequate repeater performance include vertical and horizontal spacing of the two antennas (microphone and speaker), where horizontal spacing requires ten times the distance of vertical spacing because of the antenna patterns needed for the repeater to operate. CelLynx applies proprietary technology for superior performance in the real world environment, where spacing antennas is no guarantee the repeater will behave. The system gain of the CelLynx repeater is over 65dB and the remaining sections of this paper will discuss how that translates into a superior product to be relied on anywhere close to locations with even one bar of serving signal, such as interior rooms of a home with serving signal at a window.
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Coverage is top of mind
If you plan to switch, what is the primary reason?
Source: Morgan Stanley – Equity Research, North America, Telecom Services “Extensive Survey Suggests WLNP Winners and Losers” |
What to Expect
The CelLynx repeater performs well with just one bar. That said, the coverage performance of a repeater is directly related to the signal strength of the off-the-air cellular signals arriving at the repeater antennas. Since cell phones have signal strength indicators that generally follow the same scale, this section will relate the coverage enhancement -- in square feet -- to the bars on the phone. The table below was created using a coverage prediction model, (the ITU indoor path loss model), a formula that calculates path loss with variables assigned for the environment the radio waves are propagating through. The table clearly shows that even with weak off-the-air cellular signals, a single family home of over 1,500 square feet can be adequately covered and as the signal gets stronger the coverage from a CelLynx repeater can expand significantly.
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Inside the Repeater
Patent pending design, high performance hardware, and extensive software development thrust the CelLynx repeater into the mainstream of wireless system operations. Never before has a repeater contained the attributes needed to be reliably deployed into the networks -- where people choose. The evolution of wireless communication will take an exciting leap forward now that cell phone customers are armed with not just their wireless devices, phones and data cards, but also with the CelLynx repeater to place where they want to reliably use their wireless device. Network operators will benefit from capital efficiencies with improved capacity at existing sites. The traditional fix to service complaints has been to add cell sites, when zoning and home owner associations allow, which often pose barriers. The capacity gains are relative to the improvement in signal conditions, freeing up resources to be assigned to additional connections. |
