MOTOROLA EXPEDIENCE TECHNICAL OVERVIEW
EXPEDIENCE TECHNICAL OVERVIEW a) Introduction Motorola s EXPEDIENCE Platform is an Indoor NLOS (Non Line Of Sight) Wireless Broadband platform specifically optimized for point-to-multipoint voice and data services, which provides a robust easy to install and highly scalable infrastructure for licensed frequency bands. The system provides a carrier-grade solution, allowing the operator to successfully compete against other fixed and wireless broadband access architectures. The Expedience system is a standards based wireless network platform that supports delivery of IP - compatible broadband applications, including voice and data services such as IP telephony and video streaming. Recognized for its user simplicity and immunity to multi-path interference, the Expedience system offers service providers NLOS performance, and network efficiency, without sacrificing bandwidth to achieve broad coverage. It is the first and only NLOS wireless broadband system to deliver consistent throughput across an entire cell. Subscriber Units, also known as CPE s, can be either indoor gateway units, integrated outdoor wall-mount gateways, vehicular mobile units (for instance for public safety and transportation applications) or PC Cards devices for connection to laptops. The indoor subscriber unit functions as a wireless IP gateway into the home or small-medium-enterprise (SME). This gateway enables the subscriber to run Ethernet applications on a broadband connection that can be extended locally with a Wi-Fi (hot spot) as well. The wireless IP gateway incorporates plug & play functionality. The subscriber unit is self-provisioning and does not require professional or truck-roll installation. The user simply plugs the Ethernet cable into a laptop or desktop computer and opens the browser. The user is not required to install any software, or to configure his/her laptop or PC. The platform is part of the Motorola Motowi4 portfolio, and is widely tested and extended, as a consequence of a commercial deployment for over 5 years, with more than 14.000 base stations and over 700.000 CPE s shipped worldwide. The system integrates the following technologies: Expediente Overview 2
OFDM - (Orthogonal Frequency Division Multiplex) The physical layer protocol of choice for true non-line-of-sight and 4th generation broadband networks. The OFDM solution utilizes hundreds of individual carriers and a patented process of mapping a user s data to those carriers, to actually leverage the presence of multi-path to transmit and receive robustly in the NLOS service environment. TDD - (Time Division Duplex) Upstream and downstream links on the same RF channel provides the highest flexibility in frequency utilization. No need to use multiple channels or to have guardbands between downstream and upstream channels. AMOD - (Adaptive Modulation) Enables higher capacity per sector and a robust RF link all the way to the edge of the wireless cell. AMOD can double the capacity per sector over a single modulation level. DBD - (Direct Burst Detection) The Expedience patented equalization and detection scheme eliminates the need for equalizer training sequences before sending actual data. DBD minimizes latency of user packets and optimizes the efficiency of the Expedience MAC protocol. Expedience MAC - The Expedience patented MAC architecture is the first protocol designed specifically for last mile broadband wireless data networks to optimize the scheduling and delivery of data and voice packets over a multiuser NLOS airlink. Ethernet Networking The Expedience utilizes industry standard Ethernet networking interfaces for base stations and CPEs to provide an elegant solution for scaling and managing the broadband network at both the cell site, and the enterprise or home. No need to configure base station site controllers and clunky point-to-point connection protocols, Expedience is networked and managed like other standard Ethernet networks. Expedience subscriber units plug directly to PC s or Ethernet switches/routers for simple, always-on, home or office connectivity that is compatible with existing equipment. In summary, the system provides the following key features and specifications: o Frequency Band (GHz): 2.5-2.6, 3.5 (other frequencies available upon demand) o NLOS (Non line of sight) Range: o Rural environment: up to 30 Km o Semi-urban Indoor environment: 8 Km o Urban Indoor environment: 4,5 Km o Uniform broadband data rates throughout the cell o True plug-and-play subscriber unit Expediente Overview 3
o Modulation: OFDM automatic adaptative modulation 4/16/64 QAM to maximize the capacity of the airlink. o RF Access Mode: Time Division Multiplex (TDD) o Bandwidth profiles by type of user (Service Level Agreements, SLA). o Software upgrade of service over the air. o Voice and data service capabilities available from each CPE. b) Building Blocks An EXPEDIENCE system has three main components: The Base Transceiver Station (BTS). The Customer Premises Equipment (CPE). The Network Management System. The picture below shows the architecture of the system, where the three components can be seen. Picture 3.1: Architecture of the EXPEDIENCE system. Expediente Overview 4
EXPEDIENCE BASE STATION (BTS) The BTS provides the interface between the CPE and the backbone network and between the CPE and Network Management System; it handles the CPE registration, and performs the call processing. The EXPEDIENCE BTS is designed for ease of installation in a number of different configurations, keeping costs low. The BTS is a fully self-contained, environmentally-hardened unit, which offers maximum flexibility for installation at the tower or rooftop, in an equipment enclosure, or directly mounted on a pole. The BTS features are the following: TDD transmission protocol Automated adaptative high-order modulation 4/16/64 QAM +33 dbm (2 W) RF output power (5 W RF output power available option) Network interface (IEEE 802.3 10baseT / Ethernet) IEEE 802.1q (VLAN) support Standard bases network management: SNMP, web-based, CLI and FTP Fully integrated indoor or outdoor mountable package, including all radio and modem devices. Picture 3.2 below shows the EXPEDIENCE Base Station, in the outdoor mounting on pole version. Picture 3.2: Expedience BTS Chassis. Connections to the unit include a single coaxial antenna feed, -48VDC power, 10base-T and GPS timing signal used to synchronize base stations installed in the same geographical area. Expediente Overview 5
The BTS can be used in either sectors or omnidirectional configurations, using standard antennas. Channel setup or changes can be done remotely, and requires no hardware changes on-site. A complete management of the BTS can be accomplished either by a local serial port (RS-232), telnet session, web interface or using the SNMP-based Expedience Network Management System. For a complete on-site installation, in addition to the BTS and antenna, a transient voltage suppressor (TSV) module for each BTS should be included. The TSV also allows the BTS to be powered by -48, +48 or floating 48 V power supplies. A dual redundant 48 V DC power supply is also recommended. In addition to the described devices, a GPS antenna must be installed for synchronizing all base stations in a sector and between cell to transmit and receive at the same time, making use of the 1PPS (One pulse per second) signal. The GPS antenna must be mounted on a threaded pipe or pole. The picture below shows the complete BTS installation layout, including all the necessary elements: Expediente Overview 6
Picture 3.3: Expedience BTS Installation Elements. CUSTOMER PREMISES EQUIPMENT (CPE) The EXPEDIENCE CPE device integrates the modem, the transceiver and the antenna into a single compact unit, providing indoor, outdoor and mobile fully integrated CPE s, with NLOS coverage. There are four types of subscriber units: Residential Subscriber Unit (RSU) It is a modem for indoor applications. It is a true plug&play Ethernet device, requiring no drivers to be loaded to the customer s computer. No physical installation is needed in the customer home, just connecting a power plug included. The device supports up to 15 IP addresses (static or dynamic), through a RJ-45 Ethernet interface. Expediente Overview 7
Picture 3.4: Residential Subscriber Unit. Mobile Subscriber Unit (MSU) It is a robust modem intended for mobile market applications (public safety, transportation). Power requirements are +11,7 to +15,9 V DC, adapted for a car battery supply. Picture 3.5: Mobile Subscriber Unit. Outdoor Subscriber Unit (OSU) The outdoor CPE versions (there are two) are environmentallyhardened broadband wireless modems intended for applications where a permanent mount install is required. Both units (normal and compact) are plug-and-play Ethernet devices, suited for extended range coverage. Expediente Overview 8
Picture 3.6: Outdoor Subscriber Unit (normal left ; compact right) PC Card The PC Card version delivers flexible, high-speed connectivity for nomadic wireless broadband access, providing a truly portable CPE in the form of a plug-in card for a laptop PC. As the rest of Expedience CPEs, the PC Card is a true NLOS Plug-and-Play Ethernet device, requiring on ly a simple driver to be added to the subscriber s laptop computer. The unit functions as a Network Interface Card (NIC) to the host laptop it is plugged into. It has a self-contained integrated antenna, although an external high-gain antenna can be connected to improve the radio signal. The PC Card is available only in the 2496-2690 MHz Band (2.5-2.6), with channel bandwidths of 3.5 / 5 / 5.5 / 6 MHz. There are two models, with the same performance and different physical interface: ExpressCard 54 Slot and CardBus slot. Picture 3.7: PC Card Subscriber Unit. NETWORK MANAGEMENT SYSTEM Expediente Overview 9
Motorola s Expedience NetProvision, Provisioning Management System and NetManage Element Management System provide carriers with the ability to define, manage and provision all aspects of the Expedience network. A unique feature of the Expedience system is the ability to define and provide service to multiple ISP partners that operate on the carrier s broadband infrastructure network. By distributing the access and provisioning functionalities of NetProvision, the Expedience system allows carriers to provide the ability for ISP partners to define their own SLA s and to provision their own customers on the system. The system features are the following: Automated self-provisioning XML / SOAP interface to existing CRM Local and remote diagnostics fault monitoring Over-the-air modem upgrades Provisioning managements SLA policy management Multiple ISP support Distributed and scalable architecture Simple, flexible GUI interface NetManage Element System (EMS) provides carriers with a complete set of management tools to enable the configuration, management, monitoring and reporting of all elements of the networks. It provides secured centralized and remote configuration of base stations, subscriber units and other network elements. The system reports and alerts system administrators to alarms and faults, and monitors system performance down to the individual subscriber unit. It supports customizable report generation to track network performance, utilization and capacity. The NetManage EMS consists of the Expedience EMS server and a GUI application. The distributed architecture supports standard SNMPv2 interfaces for the integration with existing OSS systems. Expediente Overview 10