This excerpt taken from the PCS 8-K filed Jun 9, 2009.
Communications between the subscriber wireless device and our network is accomplished by a frequency management technology, or air interface protocol. The FCC has not mandated a universal air interface protocol for wireless broadband systems. We and Royal Street have deployed 1xRTT CDMA technology, which is one of the dominant air interface protocols. Our and Royal Streets decision to use CDMA is based on what we believe are several key advantages that CDMA has over other air interface protocols, including higher network capacity, longer handset battery life, fewer dropped calls, simplified frequency planning, efficient migration path as our CDMA technology can be easily upgraded to fourth generation air interface protocols in a cost effective manner, and increased privacy and security. CDMA is incompatible with certain other air interface protocols. Customers and former customers of other carriers may not be able to use their wireless devices on our or Royal Streets networks because either their wireless device uses a different air interface protocol or the other CDMA carriers may have restricted the customers from changing the programming of their wireless device to allow it to be used on networks other than the original CDMA carriers network.
We also purchase EVRC-B, or 4G vocoder, handsets which will allow for greater capacity in our network and we are considering other network technology such as long term evolution, or LTE, which we believe would provide significant increases in network capacity and data rates. This technology may replace or supplement our and Royal Streets 1xRTT CDMA network.
This excerpt taken from the PCS 10-K filed May 12, 2006.
Wireless digital signal transmission is accomplished by using various forms of frequency management technology, or air interface protocols. The FCC has not mandated a universal air interface protocol for broadband PCS systems; rather, broadband PCS systems in the United States operate under one of three dominant principle air interface protocols: code division multiple access (CDMA); time division multiple access (TDMA); or global system for mobile communications (GSM). All three air interface protocols are incompatible with each other. Accordingly, a customer of a system that utilizes CDMA technology is unable to use a CDMA handset when traveling in an area not served by a CDMA-based wireless carrier, unless the customer carries a dual-band/dual-mode handset that permits the customer to use the alternate cellular system in that area.
Adequacy of 10 MHz. We believe 10 MHz of spectrum to be sufficient to begin service in metropolitan areas using technology that divides the base station coverage area served by a transmitter receiver into three parts or sectors. However, in metropolitan areas with only 10 MHz of spectrum we have a network design capable of subdividing the service area into six parts or sectors and to deploy these six-sector cells in selected, high-demand areas. Doubling the number of parts or sectors will increase the capacity of the wireless base stations in these markets by doubling the number of sectors (segments of the circle representing the base stations broadcast area) over which a base stations antennas can handle calls simultaneously.
Our vendors have informed us that cell sites using six sectors have been in operation for many years in the U.S., and we have obtained actual performance data on cell sites that have been operational for multiple years. We have commercially deployed six-sector cell sites in Miami, Sacramento, San Francisco and Tampa-Sarasota as well as in our recent launch of Detroit, and our experience with this technology has been consistent with our expectations and those of our vendors. We also anticipate that Royal Street will deploy this technology in Los Angeles and northern Florida and expect to have six-sector cell sites deployed in Atlanta and Dallas in the 3rd and 4th quarters of 2006.
We intend to further enhance network capacity by upgrading our networks with EV-DO Revision A which we forecast will be available in late 2006 or the first quarter of 2007. We believe that this technology uses spectrum more efficiently than any alternative commonly used wireless technology in 10 MHz. When combined with six-sector technology, it is our expectation that new low rate vocoder and EV-DO Revision A will more than double the effective available spectrum relative to three-sector, 1XRTT technology. Thus, we believe 10 MHz of spectrum has the effective capacity of 20 MHz using todays technologies. We anticipate that spectral efficiency will continue to improve over the next several years, allowing us to keep up with the increased usage of third-generation services.
Our decision to use CDMA is based on several key advantages over other digital protocols, including the following:
Higher network capacity. Cellular technology capitalizes on reusing discrete amounts of spectrum at a cell site that can be used at another cell site in the system. We believe, based on studies by CDMA handset manufacturers, that our implementation of CDMA digital technology will eventually provide approximately seven to ten times the system capacity of analog technology and approximately three times the system capacity of TDMA and GSM systems, resulting in significant operating and cost efficiencies. Additionally, we believe that CDMA technology provides network capacity and call quality that is superior to other wireless technologies.
Longer handset battery life. While a digital handset using any of the three digital air interface protocols has a substantially longer battery life than an analog cellular handset, battery life in CDMA handsets can provide even longer periods between recharges than other wireless technologies.
Fewer dropped calls. CDMA systems transfer calls throughout the CDMA network using a soft hand-off, which connects a mobile customers call with a new base station while maintaining a connection with the base station currently in use, and hard hand-off, which disconnects the call from the current base station when it connects to another base station. CDMA networks monitor the quality of the transmission received by multiple neighbor base stations simultaneously to select the best transmission path and to ensure that the call is not
disconnected in one base station unless replaced by a stronger signal from another. Analog, TDMA and GSM networks only use a hard hand-off and disconnect the call from the current base station as it connects with a new one without any simultaneous connection to both base stations. Since CDMA allows for both hard and soft hand-off, it results in fewer dropped calls compared to other wireless technologies.
Simplified frequency planning. TDMA and GSM service providers spend considerable time and money on frequency planning because they must reuse frequencies to maximize network capacity. CDMA technology allows reuse of the same subset of allocated frequencies in every cell, substantially reducing the need for costly frequency planning.
Efficient migration path. CDMA 1XRTT technology can be easily and cost-effectively upgraded for enhanced voice and data capabilities. The technology requires relatively low incremental investment for each step along the migration path with relatively modest incremental capital investment levels as demand for more robust data services or additional capacity develops.
Privacy and security. CDMA uses technology that requires accurate time and code phase knowledge to decode, increasing privacy and security.