A Comparative Analysis Of Wimax, Microwave Radio And Long Term Evolution (Lte) Technologies For A Broadband Internet Access Network

ABSTRACT

 This project is on comparative analysis of WiMAX, microwave radio and long term evolution (LTE) technologies for a broadband internet access network. The work presents the modern communication technology in wireless network, microwave radio, LTE and WiMAX. The system architectures between LTE, Microwave radio and WiMAX network will be shown. In addition, comparison of the system architecture and the air interface of these two networks will be discussed.

The paper further concludes with discussion of these two aspects and gives the short look into the future 4G networks.

CHAPTER ONE

1.0                                                        INTRODUCTION

With the development of high-speed mobile broadband access technology, there are three emerging technologies:

Long Term Evolution (LTE), which is developed by 3rd Generation Partnership Project (3GPP) and WiMAX, standardized by the Institute of Electrical and Electronics Engineers (IEEE).

Three of them have similar goals, specifically to provide high data rate wireless network connection for cell  phones, laptops, and other electronic devices.

Nevertheless, the system architecture of these three are different, so that the scope of applications, network services, market positions differ.

During November 2004, 3GPP launched the LTE project, which focuses on enhancing Universal Terrestrial Radio Access (UTRA) and optimizing 3GPP’s radio access architecture in order to compete with WiMAX.

In this standard, LTE is referred as the Evolved Packet System (EPS), purely IP based, which divided into two parts: the Evolved Packet Core (EPC) and the Enhanced-UMTS Terrestrial Radio Access Network (E-UTRAN).

However, LTE is also described as 3.9G as the first release of LTE did not fulfill ITU’s requirements for 4G, such as the peak data rates up to 1 Gb/s.

WiMAX can provide high data rate wireless Internet access and  telephony services for the users. The forum describes WiMAX as “a standards-based technology enabling the delivery of last mile wireless broadband access as an alternative to cable and DSL”.

Microwave radio is known as a “line of sight” technology. This is because microwave data is sent between two microwave radio towers in different locations. However, for this transmission to occur, the path between the two microwave radio towers must be clear of any large buildings, mountains, or objects. Such large objects could block microwave signals. Once a clear path has been made, transmissions between antennas on two radio towers can occur.

While LTE has focused on the needs of the current mobile operators, WiMAX is more suitable for companies, who want to have a wireless network to access the Internet. Since the goal of these three technologies is similar, they have to share the market with each other.

1.1                                         AIM / OBJECTIVE OF THE STUDY

The main objective of this work is to find the similarities and differences in these three technologies, that is, WiMAX, microwave radio and long term evolution.

1.2                                           SIGNIFICANCE OF THE STUDY

One of the significant advantages of advanced wireless systems such as WiMAX is spectral efficiency. For example, 802.16-2004 (fixed) has a spectral efficiency of 3.7 (bit/s)/Hertz, and other 3.5–4G wireless systems offer spectral efficiencies that are similar to within a few tenths of a percent. The notable advantage of WiMAX comes from combining SOFDMA with smart antenna technologies. This multiplies the effective spectral efficiency through multiple reuse and smart network deployment topologies.

Another advantages of WiMAX, is a relatively new technology that enables communication over a maximum distance of 30 miles – compared to 300 feet for WiFi. Of course, the longer the distance, the slower the speed, but it’s still faster and has a longer range than WiFi. Ideally, speeds of around 10MBps could be achieved with a range of 1 – 6 miles.

The reason why some telecommunication providers are quite excited about the prospects for WiMAX is that mobile users could use it as a faster and longer range alternative to WiFi and corporate or home users could use it in a fixed environment as a replacement or backup to DSL.

Companies will begin to use WiMAX to communicate from office to office, relatively near to each other and provide campus wide wireless connectivity to employees. Employee’s computers will need to use new WiMAX cards to connect to these new networks. Next, or at the same time, public places such as airports, parks and coffee shops will be outfitted with WiMAX access points. WiMAX has been very successful as it’s easy to use, low cost, and relatively fast.

While WiMAX has its benefits, as people download more and larger files, upload more data (such as voice calls, images and videos) and have longer distance needs – the limits of WiFi are apparent.

Residential or Home and Broadband Internet Access:

DSL and cable internet technologies are widely used in residentially and in SOHO. These technologies have strong hold on market by satisfying and meeting the needs of broadband internet users. Taking over from these users for WiMAX technology based internet may be not possible at given time, however internet provided by WiMAX bases station towers can be well utilized within the rural areas where DSL and Cable internet facilities are not available. Using WiMAX internet technology brings reliability to the customers as it being the wireless in nature there are no apparent mediums required to use it. WiMAX base station will simply connect to customer premises device and that will be all. Deploying WiMAX technology is very useful for developing countries where setup and reliability of Land line telecommunication infrastructure is poor.

In the case of microwave radio:

Large Bandwidth: The Bandwidth of Microwaves is larger than the common low frequency radio waves. Thus more information can be transmitted using Microwaves. It is very good advantage, because of this, Microwaves is used for Point to Point Communications.

Better Directivity: At Microwave Frequencies, there are better directive properties. This is due to the relation that As Frequency Increases, Wavelength decreases and as Wavelength decreases Directivity Increases and Beam width decreases. So it is easier to design and fabricate high gain antenna in Microwaves.

Small Size Antenna: Microwaves allows decreasing the size of antenna. The antenna size can be smaller as the size of antenna is inversely proportional to the transmitted frequency. Thus in Microwaves, we have waves of much higher frequencies and hence the higher the frequency, the smaller the size of antenna.

1.3                                             LIMITATION OF THE STUDY

WiMAX cannot deliver 70 Mbit/s over 50 km (31 mi). Like all wireless technologies, WiMAX can operate at higher bitrates or over longer distances but not both. Operating at the maximum range of 50 km (31 mi) increases bit error rate and thus results in a much lower bitrate. Conversely, reducing the range (to under 1 km) allows a device to operate at higher bitrates.

A city-wide deployment of WiMAX in Perth, Australia demonstrated that customers at the cell-edge with an indoor Customer-premises equipment (CPE) typically obtain speeds of around 1–4 Mbit/s, with users closer to the cell site obtaining speeds of up to 30 Mbit/s.

Like all wireless systems, available bandwidth is shared between users in a given radio sector, so performance could deteriorate in the case of many active users in a single sector. However, with adequate capacity planning and the use of WiMAX’s Quality of Service, a minimum guaranteed throughput for each subscriber can be put in place. In practice, most users will have a range of 4-8 Mbit/s services and additional radio cards will be added to the base station to increase the number of users that may be served as required.

1.3                                            APPLICATION OF THE STUDY

The bandwidth and range of WiMAX make it suitable for the following potential applications:

• Providing portable mobile broadband connectivity across cities and countries through a variety of devices.
• Providing a wireless alternative to cable and digital subscriber line (DSL) for “last mile” broadband access.
• Providing data, telecommunications (VoIP) and IPTV services (triple play).
• Providing a source of Internet connectivity as part of a business continuity plan.
• Smart grids and metering

Internet access

WiMAX can provide at-home or mobile Internet access across whole cities or countries. In many cases this has resulted in competition in markets which typically only had access through an existing incumbent DSL (or similar) operator.

Additionally, given the relatively low costs associated with the deployment of a WiMAX network (in comparison with 3G, HSDPA, xDSL, HFC or FTTx), it is now economically viable to provide last-mile broadband Internet access in remote locations.

Middle-mile backhaul to fiber networks

Mobile WiMAX was a replacement candidate for cellular phone technologies such as GSM and CDMA, or can be used as an overlay to increase capacity. Fixed WiMAX is also considered as a wireless backhaul technology for 2G, 3G, and 4G networks in both developed and developing nations.

In country, backhaul for urban operations is typically provided via one or more copper wire line connections, whereas remote cellular operations are sometimes backhauled via satellite. In other regions, urban and rural backhaul is usually provided by microwave links. (The exception to this is where the network is operated by an incumbent with ready access to the copper network.) WiMAX has more substantial backhaul bandwidth requirements than legacy cellular applications.

In many cases, operators are aggregating sites using wireless technology and then presenting traffic on to fiber networks where convenient. WiMAX in this application competes with microwave radio, E-line and simple extension of the fiber network itself.

Triple-play

WiMAX directly supports the technologies that make triple-play service offerings possible (such as Quality of Service and Multicasting). These are inherent to the WiMAX standard rather than being added on as Carrier Ethernet is to Ethernet.

Some analystsquestioned how the deal will work out: Although fixed-mobile convergence has been a recognized factor in the industry, prior attempts to form partnerships among wireless and cable companies have generally failed to lead to significant benefits to the participants. Other analysts point out that as wireless progresses to higher bandwidth, it inevitably competes more directly with cable and DSL, inspiring competitors into collaboration. Also, as wireless broadband networks grow denser and usage habits shift, the need for increased backhaul and media service will accelerate, therefore the opportunity to leverage cable assets is expected to increase.

Connecting

Devices that provide connectivity to a WiMAX network are known as subscriber stations (SS).

Portable units include handsets (similar to cellular smartphones); PC peripherals (PC Cards or USB dongles); and embedded devices in laptops, which are now available for Wi-Fi services. In addition, there is much emphasis by operators on consumer electronics devices such as Gaming consoles, MP3 players and similar devices. WiMAX is more similar to Wi-Fi than to other 3G cellular technologies.

The WiMAX Forum website provides a list of certified devices. However, this is not a complete list of devices available as certified modules are embedded into laptops, MIDs (Mobile Internet devices), and other private labeled devices.

Gateways

Many of the WiMAX gateways that are offered by manufactures such as these are stand-alone self-install indoor units. Such devices typically sit near the customer’s window with the best signal, and provide:

• An integrated Wi-Fi access point to provide the WiMAX Internet connectivity to multiple devices throughout the home or business.
• Ethernet ports to connect directly to a computer, router, printer or DVR on a local wired network.
• One or two analog telephone jacks to connect a land-line phone and take advantage of VoIP.

Indoor gateways are convenient, but radio losses mean that the subscriber may need to be significantly closer to the WiMAX base station than with professionally installed external units.

Outdoor units are roughly the size of a laptop PC, and their installation is comparable to the installation of a residential satellite dish. A higher-gain directional outdoor unit will generally result in greatly increased range and throughput but with the obvious loss of practical mobility of the unit.

For microwave radio, Microwave is used in broadcasting and telecommunication transmissions. As described above, they have shorter wavelengths and allows to use smaller antennas. The cellular networks like GSM, also uses Microwave frequencies of range 1.8 to 1.9 GHz for communication. Microwaves are also used for transmitting and receiving a signal from earth to satellite and from satellite to earth. Military or Army also makes use of Microwaves in their communication system. They uses X or Ku band for their communication.