DAS is the acronym we use in the wireless industry for DISTRIBUTIVE ANTENNA SYSTEM (DAS).

A microcell is a cell in a mobile phone network served by a low power cellular base station (tower), covering a limited area such as a mall, a hotel, or a transportation hub.  A microcell is usually larger than a picocell, though the distinction is not always clear.  Microcell’s use power control to limit the radius of its coverage area; typically the range of a microcell is less than a mile wide.  A micro cellular network is a radio network comprising of microcells.

A cellular network is a radio network made up of a number of radio cells (or just cells) each served by at least one fixed-location transceiver known as a cell site or base station. These cells cover different land areas to provide radio coverage over a wider area than the area of one cell, so that a variable number of portable transceivers can be used in any one cell and moved through more than one cell during transmission.

Cellular networks offer a number of advantages over alternative solutions:

1. Increased capacity

2. Reduced power usage

3. Larger coverage area

4. Reduced interference from other signals

A macrocell is a cell in a mobile phone network that provides radio coverage served by a power cellular base station (tower). Generally, macrocells provide coverage larger than microcell. The antennas for macrocells are mounted on ground-based masts, rooftops and other existing structures, at a height that provides a clear view over the surrounding buildings and terrain.  Macrocell base stations have power outputs of typically tens of watts. The term macrocell is used to describe the widest range of cell sizes. Macrocells are found in rural areas or along highways. Over a smaller cell area, a microcell is used in a densely populated urban area.

RF Engineering, also known as Radio Frequency Engineering, is a subset of electrical engineering. It applies to devices which are designed to operate in the Radio Frequency spectrum. RF Engineering is incorporated into almost everything that transmits or receives a radio wave which includes, but not limited to, Cell Phones, Wi-Fi and Public Safety Solutions.

RF Engineers are a part of a high;y specialized field and are an integral part of in-building wireless solutions. Their expertise is needed to design effective and reliable solutions. To produce quality results, an in-depth knowledge of mathematics, physics and general electronics theory is required. Even with this, the initial design of an RF Circuit usually bears very little resemblance to the final physical circuit produced, as revisions to the design are often required to achieve intended results.

RF Engineers are specialists in their respective field and assist in both the design, and maintenance of our solutions. Often, creative and collaborative solutions are required in the wireless industry, we work closely with our RF engineers to deliver quality solutions. The range of technologies used is vast due to the wide array of frequencies allocated for different radio services, and due to the range in age of equipment.

Each frequency range has a band designator and each range of frequencies behaves differently and performs different functions. The frequency spectrum is shared by civil, government, and military users of all nations according to International Telecommunications Union (ITU) radio regulations.

For communications purposes, the usable frequency spectrum now extends from about 3Hz to about 300GHz. There are also some experiments at about 100THz where research on laser communications is taking place but we won’t discuss this now. This range from 3Hz to 300GHz has been split into regions.

A Yagi antenna, also known as a Yagi-Uda array or simply aYagi, is a unidirectional antenna commonly used in communications when a frequency is above 10 MHz.  This type of antenna is low profile and ideal for cellular enhancement applications.

This is a data link protocol commonly used to establish a direct connection between two networking nodes.  It can provide connection authentication, transmission encryption privacy and compression.  Point to Point Connectivity is wireless can allows for the elimination of leased T-1 lines or redundancy of existing T-1 lines.  This solution is available encrypted for sensitive data as well as unencrypted and has a variety of effective applications.

In a telecommunications network the backhaul portion of the network comprises the intermediate links between the backbone, of the network and the small subnetworks at the “edge” of the entire hierarchical network.  An example would be: cell phones communicating with a single cell tower constitute a local subnetwork, the connection between the cell tower and the rest of the world begins with a backhaul link to the core of the telecommunications network.

Visualizing the entire hierarchical network as a human skeleton, the core network would be the spine, the backhaul links would be the limbs, the edge networks would be the hands and feet, and the individual links within those edge networks would be the fingers and toes.

The objective in this type of solutions is to transmit data from several distribution/access points to one centralized point of presences.  This technology offers great benefit to enterprise, particularly campus style environments such as hospitals and universities.  Harris Communications offers both licensed and unlicensed point to point and multi point solutions.

In many commercial buildings there are areas of poor wireless coverage that compromise a first responders ability to communicate.  Many municipalities have passed public safety ordinances to address the problem.

Harris Communications’ DAS solutions are custom designed to improve emergency responder communication in isolated areas or in the entire building if necessary.

There are three primary approaches to achieving in-building coverage:

1) Increasing the signal level through deployment of additional antenna sites within the jurisdiction

2) Supplementing coverage in a specific building with a permanent system that boosts the signal level received from and transmitted to the outside

3) Using deployable systems which can boost coverage in a building for a specific incident scene on a temporary basis.

There are trade offs across each of these approaches and it is likely that a combination of all three will be used in any given jurisdiction.  As a company Harris Communications is able to accommodate all three primary approaches.