Carrier BWA Infrastructure

Cost-effective last-mile solution that is fast to deploy.

Introduction

Global regulatory changes have greatly increased the number of competitors providing data and voice services. This increased competition, coupled with the dramatic increase for packet data services such as remote site connectivity, VPNs and Internet access, are driving access service providers such as incumbent and competitive carriers to upgrade and expand their networks while increasing their service offerings.

Carriers seeking a cost-effective last-mile solution that is fast to deploy are discovering the benefits of Broadband Wireless Access solutions. A wireless network can be deployed in parallel with the existing infrastructure, or as a complete infrastructure for emerging operators. Broadband Wireless Access is affordable, quick to deploy and scales easily to add capacity as customers come on-line. Broadband wireless access technologies are mature and field-proven, providing the optimal choice for operators seeking cost-savings and rapid deployment.

BWA Infrastructure

BWA solutions are implemented as a cellular infrastructure, similar to mobile telephony networks. Sectorized base stations are deployed to provide radio coverage to the targeted area, and frequency channels are reused in non-adjacent base station sectors, making most efficient use of available spectrum. Base stations are connected to the carrier central office or Point of Presence using wired or wireless point-to-point solutions. End users are provided with customer premises equipment (CPE), typically consisting of an outdoor unit with a radio and antenna, connected to an indoor unit, which receives power and presents voice and data interfaces to the customer network. The entire BWA network is connected to the carrier data backbone, the Internet and the PSTN.

Base stations have normally six sectors, but can get as low as six and up to 18 sectors. The choice of sector scheme depends on the available spectrum and subscriber density. A base station is typically deployed on a rooftop or antenna mast. The base station equipment includes both outdoor and indoor parts. The outdoor part of the base station including the radio unit and the antenna are securely installed on the antenna mast or rooftop pole. Cables connect the outdoor units to the indoor parts, located in a room on the rooftop or in a weatherproofed cabinet. The indoor parts include the base station shelf, power sources and complementary voice and data communications equipment used to aggregate and backhaul user traffic.

Alvarion BreezeACCESS Infrastructure

The Alvarion BreezeACCESS system has been designed to make BWA infrastructure deployment quick, simple and cost effective. BreezeACCESS operates in the MMDS and 3.5GHz licensed frequency bands and is also available in unlicensed frequency bands.

The Alvarion BreezeACCESS Customer Premises Equipment, known as a Subscriber Unit (SU) is installed at the customer premises and provides a standard IEEE 802.3 Ethernet 10BaseT (R-J45) connection, as well as optional POTS port. There are two main variants of subscriber units. Indoor only units can be installed at sites close to the base. Indoor/outdoor versions, consisting of an indoor unit and an outdoor unit containing the radio and antenna are required at sites located further from the base station. A single subscriber unit can support one, eight or an unlimited number of users, depending on the model.

The Alvarion BreezeACCESS base station shelf is a 19” rack mounted chassis with dual, redundant power supplies, housing up to six access unit cards. Multiple shelves can be installed in a single base station to increase capacity. A fully equipped BreezeACCESS base station can serve as many as 1000 subscribers, with each having peak throughput of up to 3 Mbits/sec and POTS telephony services. Each access unit card connects to an outdoor unit via an easily installed cable. The outdoor unit is connected to a sector antenna. The access unit card also has an Ethernet port via which it communicates with the backbone network. BreezeACCESS also features a unique standalone Access Unit, a single radio access unit for picocell deployments.

Traffic from all access units is aggregated using a standard Ethernet hub or switch. Traffic is backhauled to the carrier CO or PoP, using a variety of techniques and protocols including:

Wireless point-to-point links

• E1/T1 telco lines
• ATM IMA
• Ethernet over fiber

At the Central Office or Point of Presence, traffic is routed to/from the carrier backbone and the Internet. Telephone calls travel as data over the carrier infrastructure, optionally controlled by an IP PBX or Soft Switch. To reach the PSTN, H.323 traffic is directed to a gateway, which translates between PSTN calls and voice over IP traffic. Supplementary features such as call forward, call back and 3 party conferences can be implemented by using gateways supporting V5.2 or GR303 interfaces to the PSTN. Such gateways translate hook flash and DTMF tones to PSTN understood signaling, that initiates these advanced features.

Alvarion BreezeACCESS base stations may be deployed in macro-cell, microcell and even pico-cell deployment. Macro-cells, in which cell radius exceeds 5Km and may be as high as tens of Km, can be achieved in areas where line of sight is possible, and in deployments where all subscribers have outdoor antennas. The other extreme is a deployment, where all users have indoor-only CPEs, and there is no line of sight between base station and CPE. In such a scenario, picocells with radii of less than one Km must be deployed to give proper radio coverage to all users. The middle ground involves a deployment with cells that allow some non line of sight deployments, close to the base station and require line of sight to farther customers. Such microcells can typically cover an area with a radius of a few Km.

Traffic separation between end users, maintained in the Alvarion BreezeACCESS system using 802.1Q VLAN tagging, is preserved in the backhaul network using techniques like mapping of 802.1Q VLAN tags to ATM virtual circuits or MPLS labels. Similarly, priority of traffic is assured end-to-end in the backbone using IP ToS, or mapping 802.1p priorities to ATM circuit specifications or to MPLS labels.

Alvarion WALKair 1000 Infrastructure

The Alvarion WALKair 1000 system provides ultra-highly efficient packet data connectivity as well as carrier class TDM services via Broadband Wireless Access. WALKair 1000 operates in the 3.5GHz, 10.5GHz and 26GHz licensed frequency bands.

The WALKair 1000 CPE, or Terminal Station (TS), consists of an indoor unit, known as a Basic Unit (BU) and an outdoor unit, consisting of a radio frequency unit (RFU) and integrated antenna. The terminal station presents up to three interfaces to the user (may be most combinations of E1, Frame Relay, V.35/X.21, Ethernet) providing TDM voice and packet data services.

The WALKair 1000 Base Station is a modular hub, connected to the telecom switches on one side and to the service areas, via the Terminal Stations, on the other side. Each Terminal Station provides various Telecom services, such as leased line, ISDN, Frame Relay, Ethernet (IP) access etc., utilizing a flexible bandwidth up to 4 Mbits/sec full duplex net capacity. The entire base station provides a total network capacity of 64 E1 in 28 MHz of spectrum, which is divided among the Terminal Stations as required, using dynamic bandwidth allocation. For example 256 Terminal Stations may be connected to a single Base Station, each Terminal Station providing 4mb/s IP service, within a spectrum of just 14MHz.

The Base Station consists of several sectors; up to 8 sectors can cover a single cell. Each sector contains one or more (up to 16) Basic Units (BU), an IF MUX, RFU and an antenna.

Each BU contains up to three interfaces to the telecom interfaces, which may be E1, V.35/X.21 or Ethernet and supply for voice and data services. Each BU transmits and receives 1.75MHz carrier and handles the traffic of up to 16 Terminal Stations.

The IF MUX combines the IF signals from/to the various BUs and provides power via a single coax cable that goes up to the roof or mast top, where the RF and antenna subsystem are located. Up to 16 BUs may operate on a single RFU combined by the same IF-MUX.

The RFU converts the IF to RF, amplifies the signal to its right level and transmits it through the antenna. It is mounted near the antenna.

The Alvarion WALKair 1000 base station also includes the option of an integrated ATM access switch, allowing the transport of traffic to/from the backbone over ATM. A number of interfaces are available, including E1, IMA and optical ATM.

Alvarion WALKair 1000 base station traffic can be backhauled to the CO or PoP by a number of methods, wired and wireless. With its native E1, V.35/X.21 and Ethernet interfaces, along with the ATM access switch option, almost any media and protocol can be used.

At the CO or PoP, voice traffic is typically sent to a PSTN central office switch, where V.5 or native E1 connections are possible. Data is traffic typically connected via a router.

Alvarion WALKair 3000 Infrastructure

The Alvarion WALKair 3000 provides the ultimate in high-speed, carrier class Broadband Wireless Access communications. Operating in the 26 GHz licensed frequency band, The WALKair 3000 smoothly integrates with the WALKair 1000 system, allowing the delivery of multiple service types simultaneously.

The WALKair 3000 CPE, or Terminal Station (TS), consists of an indoor unit and an outdoor unit, consisting of a radio frequency unit (RFU) and integrated antenna. The terminal station presents up to six interfaces to the user (4x 10/100 Ethernet, 2x E1) providing voice and data services.

The WALKair 3000 Base Station indoor unit is an ETSI Shelf, connected to the ATM/IP backbone on one side and to the service areas, over the air and via the Terminal Stations, on the other side. An entire base station provides a total network capacity of 32 E3 links, totaling almost 1Gbit/second of throughput. The indoor unit is located in a controlled temperature room or shelter.

The WALKair 3000 outdoor unit includes the radio and antenna and is located on a mast or pole having clear line of sight with the outdoor units of the Terminal Stations. An IF Cable connects the indoor and outdoor units. It supports both the uplink and the downlink IF signal and provides the outdoor unit power.

The base station interfaces with the backhaul transport network using ATM STM-1 or E3 interfaces. The base station can also support IP based backbones using 10/100 Ethernet interfaces.