There are 3 types of Distributed Antenna Systems (DAS) available to enhance the cellular signal throughout a building:
- Passive DAS - no active components throughout the distribution of the signal. Once the cellular signal is connected to the system it is then distributed throughout the area needing coverage through a combination of coaxial cable, signal splitters, and antennas.
- Active DAS (base station solution/BTS) - utilizes the head-end to convert cellular signal to another transport medium such as fiber optic cable, converting it back to the original signal, then transmitting the signal through internal antennas connected in proximity of active components (remote units or hubs).
- Hybrid DAS - combination of both passive and active systems by locating all active components in the MDF/IDF, connected via a vertical fiber backbone, and distributes cellular signal over horizontal coax and strategically located antennas.
When deciding the need for one system over another, the results of a site survey will help WIN’s RF Engineers decide on which path to follow. WIN utilizes the industry leading RF planning tools to incorporate the data collected on site to ensure proper coverage requirement are met to handle voice and data. If a building is small, such as a retail store or a small office facility where only one carrier is required, then a passive system is usually sufficient. Larger buildings requiring full coverage or multiple carriers are in need of enhancing their signal, then either the active or hybrid system will be used. This selection process comes down to our RF Engineers designing the best possible solution for the carrier and customer.
WIN is also partnered with the major manufactures within the DAS marketplace. Corning|MobileAccess, SOLiD, Zinwave, Andrew|Commscope, Advanced RF, and Cellular Specialties are all considered to be leaders in the DAS industry and WIN works closely with each one to ensure we offer the best products at the most competitive prices. We are always aware of the latest and greatest products before they come to market. With our RF engineering expertise, WIN has also partaken in “first to market” trials for equipment with our manufacturers.
Carrier Relationships
The frequencies of the cellular providers are licensed and cannot be used without their knowledge and permission. WIN has a relationship with all of the major carriers across the country and we are recognized as a reputable firm that will install a DAS that satisfies carrier requirements. These systems do interact with the cellular providers’ network, and if it is not designed properly they can cause cell site outages for the carrier. Extreme care is taken during the RF engineering phase of the system design as well as the installation and commissioning to ensure that the system is as seamless as possible for the carriers. Moisture, metal, competing RF signals, large solid objects, increasingly exist in multi-tenant high rise facilities. These unavoidable variables coupled with increasing user demand for expansive bandwidth, have resulted in weak RF signal propagation within multi-tenant high rise facilities.
During the commissioning phase of the system it is imperative that the RF Engineer understands the different technologies deployed by the different carriers. Whether it is CDMA, GSM, EVDO, UMTS, LTE or AWS, there are different test criteria and metrics that require analysis to ensure the end user experiences the service that is expected in the outdoor world. WIN is always researching these technologies as well as in constant conversation with the carriers to understand these metrics. In addition to understanding the technology, WIN recognizes that each carrier and market have different requirements for their testing and standards for system approval.
