Data sheet: WL-151

Product code Product name EAN code Qty. masterpack/carton Giftbox weight Giftbox dimension Masterpack weight Masterpack dimensions Carton weight Carton dimensions
WL-151 Wireless Network PCI MIMO-XR 8716502010400 5/gr. 209(W) x 145.5 (D) x 45mm (H) 1.37 kg. 236 (W) x 218 (D) x 157 mm (H) 6.15 kg. 454 (W) x 251 (D) x 346 mm (H)
You can connect your desktop PC in no time to your wireless home network with this Wireless Network PCI card. You can then wirelessly share les, peripherals and the internet (you must have broadband subscription and a router).Thanks to new Sitecom Mimo-XR Technology you will be assured of wireless range throughout your whole house! Regardless of whether you are up in the attic or downstairs in your living room, you can enjoy the freedom of wireless networking and sur ng the net anywhere. Your connection will also be fast enough for wireless sharing of seriously large multimedia les such as digital music and movies because the WL-151 performs with actual throughput speed of no less than 35 Mbps. Sitecom Mimo-XR is backwardly compatible with the existing 802.11b/g standard. Box content: Wireless Network PCI card MIMO-XR Driver cd rom User Manual System requirements: cd rom drive Desktop with PCI slot Windows ME/2000/XP Features: Complies with both IEEE 802.11b and IEEE 802.11g products. Better coverage, less dead spaces and higher throughput with MIMO technology. Supports WMM (IEEE 802.11e QoS standard), enhance multi-media support. Supports 64/128-bit WEP, WPA (TKIP with IEEE 802.1x), WPA2 (AES with IEEE 802.1x functions for high level of security. Supports CCX 2.0 (Cisco Compatible Extensions). Supports the most popular operating system: Windows 98SE/Me/2000/XP. Supports 32-bit PCI interface. Technical specications Standard: Bus Type: Frequency Band: Modulation: IEEE 802.11g/b 32-bit PCI 2.4000~2.4835GHz OFDM with BPSK, QPSK, 16QAM, 64QAM (11g) BPSK, QPSK, CCK (11b) Data Rate: 54/48/36/24/18/12/11/9/6/5.5/2/1Mbps auto fallback Security: 64/128-bit WEP Data Encryption, WPA (TKIP with IEEE 802.1x) and WPA2 (AES with IEEE 802.1x) Antenna: Smart Antenna with Two RX and One TX (RP-SMA) Drivers: Windows 98SE/Me/2000/XP LEDs: Link, TX/RX Transmit Power: 16dBm 2dBm Receive Sensitivity: 54Mbps OFDM, 10% PER, -79dBm 11Mbps CCK, 8% PER, -90dBm 1Mbps BPSK, 8% PER, -95dBm Temperature: 32~131F (0 ~55C) Humidity: Max. 95% (Non Condensing) P. 1-1. Certication: FCC , CE

243 Mbps using channel bonding of two 40 MHz channels, and up to 135 Mbps using one 20 MHz channels. Metalink claim to be backwards compatible with 802.11a. o Atheros: Atheros announced the release of a MIMO capable variant of 802.11a/g in Jan 2005 (the AR5005VL). Atheros claims that its solution is compatible with standard 802.11a/g, and can work with multiple antennas at either or both ends of the link. It claims actual throughput of 50 Mbps when using MIMO at both ends of the link, 27 Mbps when used in mixed configurations. This compares well with the 18 Mbps that Atheros claim is realisable using conventional switched diversity. On its website it states: The AR5005VL chipset supports up to four antennas to extend range and improve network performance. Rather than rely on a proprietary pre-802.11n (pre-n) transmission method, the chipset uses multiple radio outputs to focus a coherent 802.11a/g signal towards the receiver - combining the techniques of phased array beamforming and cyclic delay diversity - in a way that is fully compatible with existing WLAN radios. The chipset also uses advanced signal processing techniques to combine multiple 802.11a/g radio inputs so as to improve overall signal strength and quality. This approach increases performance in any deployment scenario, maximizing compatibility with both MIMO and non-MIMO devices. This chipset costs ~$23 for 10,000 unit quantities. 1.3.4 Operators benchmark in terms of technology selection It is inevitable that much higher data rates will be transmitted over mobile and fixed wireless access systems over the next decade. How can such increase in data rates be achieved? SA and Other Options Most current wireless standardization bodies (3GPP, IEEE 802.11, 802.16, and 802.20) are discussing or have already included some multi-antenna techniques. This shows that the techniques are becoming sufficiently mature from both a theoretical and implementation point of view. Their practical and commercial use is a matter of engineering and marketing efforts. As a general trend, we can observe the following: o For outdoor systems, sophistication (complexity) comes first at the base station (BS) or access point (AP) side, while for indoor systems, the complexity difference between the AP and user terminal (UT) is much smaller. o The complexity ranking is in increasing order: diversity (selection diversity, combining diversity, and transmit diversity), beamforming, and spatial multiplexing. The Turning Point The crossover point is now the main issue. When does the SA option become more sensible from an operator perspective than other alternatives? SA advocates may argue that this point has been with us for some time, but carriers place a high value on real estate (tower sites) and spectrum acquisition, as these latter assets are deemed scarce and invaluable. Operators in saturated markets and some emerging mobile markets have largely exhausted these options, suggesting that the next major capacity upgrades in these areas will include SA technology. However, the individual crossover point will vary according to each operator and even according to each cell within an operators network. That crossover point is already here in 2004 for some operators as they seek to extend the life of GSM or CDMA network equipment and enhance capacity in certain high density areas. Thus, SA adoption within existing networks will be gradual and ad-hoc. Wider acceptance of the technology within cellular networks is expected to result from demand for fast data services.

4- Six sectors with 15 degree antenna.
3 sec 3 sec 6 sec 6 sec 6 sec
60 deg 54 deg 22 deg 15 deg 8 deg

Eb/No (dB)

Figure E3: Comparing Three and Six Sectors for Quality For normal operation required quality is more than -12 dB, hence the best quality is in the following order: 1- Three sectors with 54 degree antenna. 2- Three sectors with 60 degree antenna. 3- Six sectors with 22 degree antenna. 4- Six sectors with 15 degree antenna. 5- Six sectors with 8 degree antenna. The essence of the results is that with proper choice of antennas, six-sector coverage and performance can be comparable to three-sector quality, though a bit reduced. It is not a simple task to translate such a reduction in coverage and performance to reduction in capacity from the theoretical limit of twice the 3-sector. However, a 10~25 % decrease was obtained rendering the final result as: Capacity (6-sector) = (1.8~ 1.7).Capacity (3-sector) Finally, with conventional antennas, six-sector can require as many as eighteen antennas, each of which must be precisely aligned in order for the site to operate properly. With a smart antenna system, as few as three antennas do the job, regardless of whether the site is configured for three, four, five or six sectors. Six-sector requires two base station radios, but with conventional antennas, it also requires twice the power amplifiers, duplexers, filters and cabling compared to three-sector. Because a smart antenna system manages the RF signal flow from the base stations all the way to the antennas, no additional amplifiers, duplexers, filters or cabling is required, resulting in significant cost savings.
Performance In terms of Capacity Gain, QoS, and Spectrum Utilization
UMTS/ CDMA2000 System Consider wireless communication system which combines: 1) multiple transmit signals; 2) adaptive modulation for each signal; and 3) adaptive array processing at the receiver. Assume a noise-limited environment, corresponding to either an isolated cell or a multicell system whose out-of-cell interference is small compared with the thermal noise. We focus on the user data throughput, in bits per second/Hertz (bps/Hz), and its average over multipath fading, which we call the user spectral efficiency. First, an analysis method is developed to find the probability distribution and mean value of the spectral efficiency over the user positions and Smart Antennas in Fixed Wireless 13 of 141
shadow fading, both as a function of user distance from its serving base station and averaged over the cell coverage area. Next, Monte Carlo simulation is used both to confirm the analysis and to treat cases less amenable to simple analysis. Table E1: Mean spectral efficiency bps/Hz System Mean Spectral Efficiency (bps/Hs) Ideally coded SISO system 9.25 (1,1) Un-coded 6.67 Ideally coded SIMO system 11.5 (1,3) Un-coded 8.93 Ideally coded MIMO system 23.14 (3,3) (with Un-coded MMSE) 15.4 Table E1 shows the mean spectral efficiency for various cases. A few key points can be extracted from these results: The mean spectral efficiencies attainable with MIMO systems (15.4 to 23.14 bps/Hz) go far beyond those of single-input multiple-output (SIMO) systems (8.93 to 11.5 bps/Hz) and single-input single-output (SISO) systems (6.67 to 9.25 bps/Hz), which confirms results from the literature. MIMO systems provide two types of gain depending on the system: spatial multiplexing TableE2: Gain in SNR and gain in average capacity, for diversity-based and SM-based MIMO systems over SIMO system (short-term averaged input SNR = 15 dB) 2x2 vs. 1x2 Gain in SNR (dB) Gain in average Capacity MIMO-div vs. SIMO MIMO-SM vs. SIMO 3.3 46% 2x.3 vs. 3x3 vs. 1x3 1x3 2.5 59% 3.6 94% 3x4 vs. 1x4 3.0 110% 4x4 vs. 1x4 3.6 140%

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Mobility aspects and common channel requirements: Obviously, the channel characteristics vary significantly according to the service model. One particular issue in mobile networks is cell to cell handover. In CDMA systems some capacity is lost due to the soft handover areas between cells. In the downlink, this has the effect of increasing interference by making multiple transmissions to a user terminal from more than one base station and in the uplink for one users transmissions to contribute to other users interference in more than one cell. The extent of the overlap area is dependent upon the speed at which handover can be affected and the user terminal speed. These set a limit on the gains that can be realized by increasing the number of fixed sectors in a cell. Whilst beam-steering can be used with adaptive beamformers, mobility management aspects would need to accommodate users whose angular speeds or directions differ. Clearly these issues are not relevant for fixed wireless access systems where high gain switched beam and adaptive antennas have already been successfully deployed. Whilst techniques exist to improve cell range for dedicated channels, it is essential that the communications link is balanced in both uplink and downlink directions and for both common and dedicated channels. The requirement to increase common channel range can be particularly problematic, since the common channels need to cover the entire cell, not just high gain in the direction of a given user. Whilst a rotating high gain common control beam can be used to sweep around a cell, this has the effect of reducing the common control capacity to any given location in the cell. Since common control capacity can limit system performance in existing 2G networks, this is clearly a serious consideration for any technique that seeks to increase cell range; unless the common channel capacity demand is low, the environment changes slowly or the link is tolerant of some increased delay (such as with WLANs). Support within the air interface and MAC protocol: Retrospective application of some smart antenna techniques can be difficult or impossible to achieve. Whilst retrospective provision of hardware at a base station can be costly, retrospective provision of the hooks in the air interface definition necessary to support the information exchange or to facilitate low complexity in the transceivers can be prohibitive. One feature included in UMTS to support beamforming type antennas was the inclusion of dedicated pilot channels. These allow that channel assessment on a dedicated pilot channel using a particular beam pattern is representative of the channel responses on other dedicated channels using the same beam response which would not be the same if the omnidirectional common pilot channel was used to determine the channel characteristics. It is therefore of significant interest to note that the performance benefits of MIMO are sufficiently large that a large part of the standard definition of Release 7 of the UMTS standard is specifically to support MIMO. General consensus at the aforementioned RAN evolution workshop was that future air interfaces would be based upon OFDM and MIMO techniques and it is likely that these will be an integral part of any system defined in the short term future. Any model that is intended to determine the system performance benefit of a smart antenna system must clearly consider the influence of all of the above factors, in both uplink and downlink directions. The computational complexity is such that any network performance model which seeks to incorporate the detailed physical layer and signal detection algorithms 37 of 141

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Multi-antenna handsets are being designed and so are video routers. The evolution of MIMO into cellular base stations is expected to boost capacity by 4x to 7x with fewer dropped calls and better coverage at the cell's edges. Similarly, WiBro is expected to add MIMO modes to its evolving specification. Others are sure to follow and MIMO looks like the wireless communications industry's best bet to make good on its "faster-than-wired" promises. 2.2.4 Path to 4G Cellular Since its inception, CDMA has been a revolutionary technology. Due to CDMAs superiority over other standards like GSM, Qualcomm not only drove the standards for 3GPP2 but also penetrated into the 3GPP WCDMA standards. CDMAs huge success has helped Qualcomm extract significant royalties from handset OEMs. But, recently, OFDM has been gaining ground and emerging as the new disruptive technology of the future. OFDM has achieved this distinction by its ability to handle the common radio frequency distortions without the need for complex equalization algorithms and its ability to easily scale in the spectrum domain. During last few years, OFDM technology has been successfully applied to number of wireless applications like WLAN, Broadcasting (DVB), and WiBro/WiMAX. Recently, a startup, Flarion, proved the promise of OFDM for cellular applications with burst rates for downlink up to 3.2Mbps. Realising the potential of OFDM as the technology for 4G standards, Qualcomm acquired Flarion. The acquisition indicates that OFDM is the technology of the next generation. MIMO technology is at various stages of adoption or deployment in third generation cellular systems, broadband fixed wireless systems, high speed WLAN and mobile ad-hoc networks. Based on Airgos pioneering efforts, economical MIMO OFDM based WLAN systems became a reality in 2003 and this set a new course for the wireless industry. MIMO-OFDM will be the basic modulation format for 802.11n Wireless LAN (WLAN) since every proposal submitted for this standard uses MIMO-OFDM as the primary method to achieve significantly greater range and throughput over 802.11a or 802.11g. 2.2.5 Widespread Acceptance Over the past few years, MIMO technology has penetrated a variety of other important commercial wireless markets besides WLAN. Multiple MIMO based standards are being envisioned for the cellular frontier. MIMO is already being standardized as part on the 3GPP roadmap for HSDPA and WCDMA. WiMAX broadband wireless access networks and 3G cellular mobile networks have already adopted MIMO as an optional mode of operation for performance enhancement. MIMO-OFDM is being proposed and implemented as part of WiBro and is already part of the feasibility study for 3GPP LTE standard. A clear majority of companies proposed OFDM based downlink for 3GPP LTE (Long Term Evolution) meeting held in Beijing. A number of major handset and network providers are developing and lab-testing MIMO OFDM based cellular systems for next-generation networks. Tests conducted by Nortel, Ericsson, Motorola, Siemens, etc have shown the promise of the technology. 2.2.6 Implementing MIMO Airgos success in developing and launching MIMO based WLAN chipsets, has proven that MIMO is highly effective in enhancing the data rates and coverage over the standard OFDM

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Smart antennas in WLANs
A large number of companies offer WLAN-type products that claim to benefit from smart antennas and/or smart technologies in their products. There are a wide variety of methods and manufacturers operating in the WLAN sector, and many are offering capability that is ahead of formal adoption by the standards body in the competition to gain early market entry for a superior technology. An advantage of WLAN systems such as the 802.11 series is that, assuming that the Carrier Sense Multiple Access/ Collision Avoidance resolves multiple access to a given access point, only one transmitter is active on a given Basic Service Set (BSS), i.e. cell, at a time. Hence there is no need to use MUD techniques at the receiver. Cochannel interference from users and access points that form alternative BSSs is a major concern in some environments. Key performance advantages promoted by many of the major players are summarized below. Enterprise Solutions: o Vivato: Vivatos VP2200 and VP2210 base stations use up to 6 steerable beams, in a 90 sector, to increase base station coverage to standard Wi-Fi 802.11 b/g terminals. Vivato see the main benefit being extended range, which reduces the overall number of access points required to cover a given metropolitan/office/industrial environment. This reduces installation and management costs. The mechanism by which Vivato scans or steers beams that have an extended range compared to broadcast channels on traditional omni-directional antennas is not clear. Appliqu Solutions: o Motia: Motias Javelin analogue beamforming appliqu uses 4 antennas and claims to increase range by 2 or 3 times (or 3 to 4 times if fitted at both ends of the link) for 802.11b/g systems. This solution is expected to add ~$20 to the cost of a Wi-Fi access point. The appliqu uses analogue spatial filtering with beam selection and switching in the first 2uS of the burst (time dictated by 802.11a/g air interface), with switching on a per packet basis. Since 802.11b/g are TDD systems, the same weight table is used for the return link. Beam switching solutions: o Airgain: Airgain market 802.11b/g routers and access points that appear to use switched beam methods with patch antennas to provide 10dBi gain. It is not clear from their website how this device supports links to multiple users whose signals have different arrival angles at the base station, or how the broadcast channel and access channels achieve the same range. Diversity receiver systems: o CSR: CSR recently announced its UniFi single chip solution for 802.11a/b/g. This device includes dual receive chains at both 2.4GHz and 5GHz bands to support a diversity combining scheme. The combining scheme is not clear but is assumed to approximate optimum combining. This device has a target price of < $10; the antenna configuration is not critical and is expected to be deployed in mobile devices. Other methods of improving performance:

The Turning Point

The crossover point is now the main issue. When does the SA option become more sensible from an operator perspective than other alternatives? SA advocates may argue that this point has been with us for some time, but carriers place a high value on real estate (tower sites) and spectrum acquisition, as these latter assets are deemed scarce and invaluable. Operators in saturated markets and some emerging mobile markets have largely exhausted these options, suggesting that the next major capacity upgrades in these areas will include SA technology. However, the individual crossover point will vary according to each operator and even according to each cell within an operators network. That crossover point is already here in 2004 for some operators as they seek to extend the life of GSM or CDMA network equipment and enhance capacity in certain high density areas. Thus, SA adoption within existing networks will be gradual and ad-hoc. Wider acceptance of the technology within cellular networks is expected to result from demand for fast data services. Consumers in most parts of the world are just beginning to use such services, and broad acceptance of mobile Internet is likely five years or more in the future, suggesting that SA deployments will accelerate dramatically as we approach this milestone. SAs and MIMO are technologies that compete with other types of network enhancements. Investments in SAs and MIMO pay off as soon as the traffic demands come close to the capacity limits without antenna array enhancements. Conversely, SAs have the capability to save sites when deploying a new network. The cost structure of such investments is highly relevant to operators. The ratio between the time-averaged cost of the equipment and the costs per site define the merits of SAs/MIMO. Key technological challenges include: moving portions of the baseband processing and the power amplifiers close to the antenna array, integrating multiple antenna elements into small device volumes, and mastering the numerical complexity of signal processing and radio resource management strategies. SAs have already been on the market for more than 20 years, while MIMO systems have recently been introduced. However, both SA and MIMO techniques are not in wide use yet. Two standards, IEEE 802.16e, released in 2005, and 802.11n, expected in 2007, with SA and MIMO as essential components. In 2007, the standard compliant products may first gain a significant share of the laptop market. Although SAs at large are not widely deployed, switched diversity as a simple SA technique is already in common use in WLAN and 2G base stations. Advanced techniques such as transmit beamforming and space-time codes are being incorporated into 3/4G UMTS and 802.16d/e standards. Theoretical study and system development of MIMO in the last decade cleared major technical obstacles for market deployment. A few products were already deployed in 2003 and 2004. However, additional costs, competition with existing non-MIMO systems, and delayed standardization processes prevented MIMO from penetrating the market. Since laptop is a better platform for high-data-rate applications such as video streaming, we expect MIMO on laptops may take the first stronghold in the marketplace in 2007 in the form of 802.11n and later 802.16e compliant products. Non-MIMO SA technology has already been introduced in cellular systems, such as the Alamouti-type transmit diversity techniques (STTD and STS) that were incorporated almost five years ago in the 3GPP and 3GPP2 standards, respectively. However, the introduction of true MIMO systems in commercial 3G (macro-cellular) systems has so far stalled. Some

Fig. 3.11: Expected coverage for five different antennas when operating in a system of 8 cells For Normal operation signal strength required is between -60 ~ -120 dBm, hence, the best coverage is in the following order: 1- Three sectors with 54 degree antenna 3- Six sectors with 22 degree antenna. 5- Six sectors with 8 degree antenna. 2- Three sectors with 60 degree antenna 4- Six sectors with 15 degree antenna.

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AREA -50 ~ - -12 ~ -6 -6 ~ --4 ~ -2 -2 ~ 0 0~2 2~4 4~sec 60 deg 3 sec 54 deg 6 sec 22 deg 6 sec 15 deg 6 sec 8 deg
Fig. 3.12: Expected quality for five different antennas when operating in a system of 8 cells For normal operation required quality is more than -12 dB, hence the best quality is in the following order: 1- Three sectors with 54 degree antenna. 2- Three sectors with 60 degree antenna. 3- Six sectors with 22 degree antenna. 4- Six sectors with 15 degree antenna. 5- Six sectors with 8 degree antenna.

Quality CDF

1.0.8 CDF 0.6 0.4 0.-10 -dB 60cum 54cum 22cum 15cum 8cum
Figure 3.13: Comparing three and six Sectors Quality base on CDF when operating in a system of 8 cells The essence of the results is that with proper choice of antennas, six-sector coverage and performance can be comparable to three-sector quality, though a bit reduced. It is not a simple task to translate such a reduction in coverage and performance to reduction in capacity from the theoretical limit of twice the 3-sector. However, a 10~25 % decrease was obtained rendering the final result as:
Capacity (6-sector) = (1.8~ 1.7).Capacity (3-sector) Finally, with conventional antennas, six-sector can require as many as eighteen antennas, each of which must be precisely aligned in order for the site to operate properly. With a smart antenna system, as few as three antennas do the job, regardless of whether the site is configured for three, four, five or six sectors. Six-sector requires two base station radios, but with conventional antennas, it also requires twice the power amplifiers, duplexers, filters and cabling compared to three-sector. Because a smart antenna system manages the RF signal Smart Antennas in Fixed Wireless 76 of 141
flow from the base stations all the way to the antennas, no additional amplifiers, duplexers, filters or cabling is required, resulting in significant cost savings. 3.1.3 Smart Antenna Systems
In the late 1990s, the limitations of broadcast antenna technology on the quality, capacity, and coverage of wireless systems prompted an evolution in the fundamental design and role of the antenna in wireless systems. Sectorization was the first step toward increased spectral efficiency in wireless networks. The next step in this evolution has been the development of the smart antenna, also known as the intelligent antenna. Although directional antennas and sectors multiply the use of radio channels, they do not overcome the major disadvantage of standard antenna broadcast co-channel interference. Standard antennas also compensate for a lack of knowledge of end user whereabouts by simply boosting the RF power levels of signals they broadcast. This approach could generate interference with signals in the same or adjoining cells. Sector (directional) antennas provide increased gain over a restricted range of azimuths when compared to an omni antenna. This is commonly referred to as antenna element gain but should not be confused with antenna processing gains (i.e., software management of signals) with smart antenna systems. The management of co-channel interference is the number one limiting factor in maximizing the capacity of a wireless system. To combat the effects of co-channel interference, smart antenna systems focus directionally on intended users and in many cases even direct intentional nulls toward known, undesired users. Think of a null as an empty signal. The goal of a smart antenna system is to increase the signal quality of the radio-based system through more focused transmission of radio signals while enhancing capacity through increased frequency reuse. When spectrally efficient solutions are a business imperative, as they are today, smart antenna systems can provide greater coverage area for each cell, higher rejection of interference, and substantial capacity improvements. Generally speaking, each type of smart antenna system forms a main lobe toward individual users and attempts to reject interference or noise from outside of the main lobe. Smart antennas are designed to help wireless operators cope with variable traffic levels and the network inefficiencies they cause. These systems also allow carriers to change gain settings to expand or contract coverage in highly localized areas all without climbing a tower or mounting another custom antenna. Wireless carriers can then tailor a cells coverage to fit its unique traffic distribution. If necessary, carriers can modify a cells operation using smart antennas based on the time of day or the day of the week or to accommodate an anticipated surge in call volume from a sporting or community event. Usually collocated with the base station, a smart antenna system combines an antennas array with a digital signal-processing capability to transmit and receive in an adaptive, spatially sensitive manner. In other words, this type of system can automatically change the directionality of its radiation patterns in response to its signal environment. They can increase the performance of a wireless system dramatically. Smart antenna systems fall into two main categories: switched-beam systems and adaptivearray systems. Generally speaking, each approach directs a main lobe (or radio beam) toward individual users and attempts to reject interference or noise from outside of that main lobe.

comprehensively and transmit more selectively. This approach continuously updates its transmission strategy based on changes in both the desired and interfering signal locations. Among the most sophisticated utilizations of smart antenna technology is an adaptive-array technology known as SDMA. SDMA employs advanced processing techniques to basically locate and track fixed or mobile terminals, adaptively steering transmission signals toward users and away from interferers. This adaptive-array technology achieves superior levels of interference suppression, making possible more efficient reuse of frequencies than standard fixed hexagonal reuse patterns. In essence, SDMA can adapt the frequency allocations to where the most users are located. Utilizing highly sophisticated algorithms and rapid processing hardware, spatial processing takes the reuse advantages that result from interference suppression to a new level. Spatial processing dynamically creates a different sector for each user and conducts frequency/ channel allocation in an ongoing manner in real time. To process information that is directionally sensitive requires an array of antenna elements (usually 4 to 12 where the inputs from each element are combined to control signal transmission adaptively). Antenna elements can be arranged in linear, circular, or planar configuration and are most often installed at base stations (though they could be used in mobile phones or laptop computers as well).
Summary of Smart Antenna Systems The distinctions between the two major categories of smart antennas relate to the choices in transmit strategy: Switched-beam antennas use a finite number of fixed, predefined patterns or combining strategies (sectors). As a mobile moves throughout a macrosector, wireless calls are switched from microsector to microsector. Conversely, adaptive array antennas use an infinite number of scenario-based patterns that are adjusted in real time, steering the lobe with the user as they move through the sector. Both systems attempt to increase gain according to the location of the user. Only the adaptive system provides optimal gain while simultaneously identifying, tracking, and minimizing interfering signals. Switched beam and adaptive-array systems share many hardware characteristics and are distinguished primarily by their adaptive intelligence. With some modifications, smart antenna systems are applicable to all major wireless protocols and standards. Switched-beam solutions work best in environments with minimal to moderate cochannel interference and have difficulty distinguishing between a desired signal and an interferer. Adaptive-array technology offers more comprehensive interference rejection. Because it transmits an infinite number of combinations, its narrower focus creates less interference to neighboring users than a switched-beam approach. Simple antennas work for simple RF environments. However, smart antenna solutions are needed as the number of users, instances of interference, applications, and propagation complexity grow. Their smarts are contained in their digital signal-processing facilities. Although smart antenna technologies are promising many benefits, they do have some disadvantages. The main drawbacks of smart antenna systems are increased base station complexity, increased need for computational power, and more complex resource management schemes. But the single biggest disadvantage to these systems today is their cost. The average cost of standard (or dumb) base station antennas is around $500. In contrast, smart antennas can cost up to around $4,500 each. This high cost has precluded their widespread deployment in wireless systems today. Smart antennas have not been extensively 79 of 141

For the introduction of beamforming techniques to be viable, reduced quantities of sites and other network elements leading to cost savings in network deployment, should outweigh the costs of deploying beamforming antenna techniques. However, the overall savings depend upon the scale of rollout and the nature of the business. We have evaluated the economic benefits of using beamforming antennas from an operators perspective by considering a range of practical rollout scenarios (with and without beamforming antennas) and have assessed the resulting cost savings relative to total typical business costs faced by operators.

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Services
The simulated service was a BFWA network, which delivers communications to residential and small business subscribers by wireless transmission from a network of base station sites. Subscribers were assumed to be issued with small, portable antenna units known as Customer Premises Equipment (CPE) which connect directly to their PC. Each CPE antenna unit utilized a directional antenna that was aligned to the base station supplying the strongest signal either by customer alignment or intelligent automatic switching of sectorized antenna elements. The simulated service delivered to the subscriber was essentially an IP pipe having a throughput to an individual CPE that can vary from 80kbit/s to 19 MBit/s, although it aimed to ensure that a rate of 2 Mbit/s was achievable at the edge of coverage. The actual instantaneous bit rate demanded by a CPE depended upon the applications being used at that time. The probability of a service being active in the busy hour is a function of the total busy hour volume of traffic demanded by the subscriber and the minimum throughput rate for that service. The Busy Hour Activity Factor defined this probability for each service. The usage forecasts in Table 8 were derived by using typical values for services of this type. Each service was defined by its minimum throughput and its delay sensitivity. Within the simulation, delay sensitivity was used very simply. If a service had high delay sensitivity then we ensured that there was sufficient network resource to allow adequate Grade of Service (GoS) for the call to be established. Where a service had low sensitivity then we assumed that traffic would be queued in the network or CPE when congestion occurs. 5.1.5 WiMAX system aspects The WiMAX network assumed for the analysis was based on a cellular system, where sites are deployed in a regular pattern with each site serving three sectors. The coverage areas of the sectors form a tessellated hexagon pattern. In each sector a number of TDD channels using discrete frequencies are used for communications with CPE within its coverage area. Each channel allows simultaneous sessions from a number of CPE to be time multiplexed onto the channel in both the uplink and downlink directions. An important parameter in TDD systems is the level of asymmetry applied to the channel. We have assumed that one third of the channel time would be devoted to uplink communications and two thirds to downlink, and that this would be synchronized across the network. This reflects the asymmetry implicit within the usage assumptions in Table 9. The WiMAX system is highly flexible in its ability to be configured for a mix of services. Any communications path can be assigned as much of the channel as required and the Modulation and Coding Scheme (MCS) is adjusted to maintain the best throughput possible for the available Carrier to Interference Ratio (CIR). Therefore the amount of the channel that a CPE occupies depends upon the services demanded at that instant and the CIR that is available at the CPE and base station receivers. The WiMAX system is able to change MCS within a frame according to the CIR available at any location and time. The CIR requirements and throughput assumptions are detailed in Table 5.1

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20. M. Yavuz, D. Paranchych, G. Wu, G. Li and W. Krzymien, Performance Improvement of the HDR System due to Hybrid ARQ, 54th IEEE Vehicular Technology Conference, vol. 4, pp. 2192-2196, 2001. 21. W. Xiao, R. Ratasuk, A. Ghosh, K. B. Love, "Scheduling and Resource Allocation of Enhanced Uplink for 3GPP W-CDMA" Proc. of PIMRC, Berlin, Germany, Sept. 2005 22. Hujun Yin and Siavash Alamouti, OFDMA A Broadband Wireless Access Technology, IEEE Proc. of Sarnoff Symposium, March 2006. 23. P. Rysavy, Hard Numbers and Experts Insights on Migration to Wireless 4G Technology pp. 9-16, Feb 27, 2005 24. S.M. Alamouti, A Simple Transmit Diversity Technique for Wireless Communications, IEEE Journal on Selected Areas in Communications, vol. 16, pp 1451-1458, October 1998. 25. V. Tarokh, H. Jafarkhani and A. R. Calderbank, Space-time Block Codes from Orthogonal Designs, IEEE Transactions on Information Theory, vol. 45, pp. 1456-1467, July 1999. 26. G. J. Foschini, Layered Space-Time Architecture for Wireless Communication in a Fading Environment When Using Multielement Antennas, Bell Labs Tech. J. pp. 41-59, Autumn 1996. 27. G. J. Foschini, G.D. Golden, P.W. Wolniansky and R.A. Valenzuela, Simplified Processing for Wireless Communication at High Spectral Efficiency, IEEE. Journal on Selected Areas in Communications, vol. 17, pp. 1841-1852, 1999. 28. 3GPP TSG-RAN-1, "Effective SIR Computation for OFDM System-Level Simulations," R1-031370, Meeting #35, Lisbon, Portugal, November 2003. 29. 3GPP TSG-RAN-1, System-Level evaluation of OFDM - further Considerations, R1-031303, November 17-21, 2003. 30. 3GPP2 C.R1002-0, CDMA2000 Evaluation Methodology, December 2004. 31. 3GPP TSG-RAN-1, "Effective SIR Computation for OFDM System-Level Simulations," R1-031370, Meeting #35, Lisbon, Portugal, November 2003. 32. D. Kitchener, W. Tong, P. Zhu, M. Jia, D. Yu, J. Ma, M.H. Fong, H. Zhang and B. Johnson, Simplified Link Level MIMO Channel Model, IEEE 802.16e, April 2004. 33. P. Bender, P. Black, M. Grob, R. Padovani, N. Sindhusayana, A.J. Viterbi, CDMA/HDR: A Bandwidth-Efficient High-Speed Wireless Data Service for Nomadic Users, IEEE Communications Magazine, vol. 38, no. 7, pp. 70-77, Jul. 2000. 34. W. Xiao, F. Wang, R. Love, A. Ghosh and R. Ratasuk, 1xEV-DO System Performance: Analysis and Simulation, Proceedings of VTC Fall 2004. 35. R. Love, W. Xiao, A. Ghosh, and R. Ratasuk, Performance of 3GPP High Speed Downlink Packet Access (HSDPA), 60th IEEE Vehicular Technology Conference, vol. 5, pp. 3359-3363, Los Angeles, Sept 2004. 36. WiMAX Forum website, Mobile WiMAX Part II: A Comparative Analysis, 2006.

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APPENDIX A
Airgo Networks, Inc. Products and Technology Airgo develops and sells chipsets; software and reference designs that change what consumers can do with wireless networking and vastly improve the quality and convenience of the wireless experience. Airgo is first-to-market with MIMO-enhanced, 802.11 a/b/gcompliant solutions. Airgo-based products feature: o 100% Wi-Fi compatibility and interoperability o simultaneous improvements in coverage, speed and reliability o spectral efficiency and global regulatory compliancy o cost and power efficient designs Airgo has taken MIMO from original concept, to industry standardization, global regulatory certification and mass market realization. Products
1. Buffalo Technology MIMO240 Wireless Cable/DSL Router (MPN: WZRG240) Price Range: $116.72 - $160.00 from 29 Sellers Description: Buffalo AirStation MIMO 240 Wireless Router WZR-G240 offers up to 10X faster wireless throughput than a standard 802.11g router. Airgo Gen-3 MIMO technology utilizes multiple antennas to transmit and receive multiple wireless signals simultaneously, resulting in a faster and more reliable wireless network than conventional wireless solutions. With Adaptive Channel Expansion (ACE) technology, the AirStation MIMO 240 wireless solutions automatically detect and adjust to interference allowing for maximum wireless throughput in any environment. In addition to improved performance, the AirStation OneTouch Secure System (AOSS) allows you to set up a high-speed secure wireless network within minutes. With 10/100 switch, you can add up to 4 LAN connections. The AirStation MIMO 240 Router is a great solution for multimedia streaming offering high-speed wireless performance. PRODUCT FEATURES: MIMO 240 Technology (Multiple In, Multiple Out), Great for High-Speed Multimedia Streaming or Online Gaming, Easy Setup with AirStation One-Touch Secure System, High Security with WPA-PSK(AES)amd 128/64-bit WEP, Backward Compatible with IEEE 802.11g/b, Includes NAT/SPI Firewall and Intrusion Detector, Dynamic Packet Filtering, Built-in DHCP Server, Built-in 4-Port 10/100 Switch, High-Speed Routing Throughput (Supports FTTH).

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2. ASUS WL566gM MIMO Wireless Router (MPN: WL566GM) Price Range: $108.99 - $132.99 from 13 Sellers Description: With Advanced MIMO technology, the WL-566gM leveraged advanced digital signal processing to deliver the highest signal sensitivity, best coverage, and enhance actual speed up to 100Mbps.
3. Linksys Wireless-G PCI Adapter with SRX400 (MPN: WMP54GX4) Price Range: $86.01 - $117.00 from 25 Sellers Description: the linksys wireless gpci adapter with srx400 installs in most desktop and tower pcs, and lets you put your computer almost anywhere in the building without the cost and hassle of running network cables. Now you don't have to drill holes in your walls and climb through the attic or cellar to get connected to the network. the wireless-g pci adapter with srx400 combines smart antenna technology with standards-based wireless-g (802.11g) networking. By overlaying the signals of two wireless-g compatible radios, the ""multiple in, multiple out"" (MIMO) technology effectively doubles the data rate. Unlike ordinary wireless networking technologies that are confused by signal reflections, MIMO actually uses these reflections to increase the range and reduce ""dead spots"" in the wireless coverage area. The robust signal travels farther, maintaining wireless connections up to 3 times farther than standard wireless-g. with srx, the farther away you are, the more speed advantage you get, and srx400 works great with standard wireless-g and -b equipment, and other flavors of linksys SRX. But when both ends of the wireless link are srx400, the network can increase the throughput even more by using twice as much radio band, yielding speeds up to 10 times as fast as standard wireless-g- faster than 10/100 wired network speeds! But unlike other speed-enhanced technologies, srx400 can dynamically enable this double-speed mode for srx400 devices, while still connecting to non-srx400 wireless devices at their respective fastest speeds. And srx400 is a "good neighbour", always checking for other wireless devices in the area before gobbling up the radio band. Once you're connected, you can surf the web, keep in touch with your e-mail, and share files and other resources such as printers and network storage with other computers on the network. To protect your data and privacy, your wireless connection is protected by up to 128-bit encryption. The included set-up wizard will walk you through configuring the adapter to your network's settings, step

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o With net 7 dB link budget gain, helps 3G operators achieve 70% reductions in the cost of HSDPA coverage o Enhances coverage at rollout through combining and diversity gains o Improves capacity as networks mature through interference mitigation o Clean, modular software interfaces for easy incorporation into Node B architectures The WCDMA/HSPA Challenge As you extend your WCDMA/HSDPA network to increase suburban and rural coverage, you will face network economics challenges many 3G operators are now experiencing in this transition. A common goal is to minimize capital costs by using existing 2G sites. Unfortunately, given the shorter range of HSDPA, this approach often leaves gaps in coverage that can only be filled with additional sites. ArrayComms A-MAS Answer for Suburban and Rural HSPA Coverage ArrayComm has developed A-MAS for WCDMA/HSDPA to help solve this problem. Most conventional deployments today use three sectors and two antennas in each two for receive and one for transmit. In ArrayComms A-MAS design, these six directional antennas are replaced with six omni antennas, all driven by a single MAS-enabled node B. This relatively simple change has a dramatic effect on network economics. Tower-top mechanical complexity is held constant, total radio equipment capital and operating costs per site fall, range increases by 60% or more, and the net costs of coverage per unit area falls by more than 70%! A-MAS for WiMAX Client Device Product at a Glance o Complete multi-antenna signal processing (MAS) software implementation for WiMAX client devices, including AAS and MIMO o Enhances MIMO Matrix A and B processing with interference mitigation, yielding 2x data rates, 1015 dB link budget improvement over SISO baseline, and spectral efficiency of ~4 bps/Hz o Includes MAS processing software and system architecture guidelines o Clean, modular embedded software or synthesizeable core interfaces (see logical diagram below) o Fully compliant with WiMAX Forum 802.16e implementation profiles As wireless industry momentum continues to build around WiMAX, recognition is growing that mult-antenna signal processing (MAS) architectures will play a pivotal role in the technologys success. In fact, the operators and manufacturers in the WiMAX Forum defining implementation profiles for 802.16e have concluded that support for MAS is mandatory for mobile WiMAX equipment. ArrayComm has been collaborating in the WiMAX community for the past two years to enhance support for MAS in the 802.16 standards as well as more recently in the mobile WiMAX profile definitions. These efforts have enabled the development of our complete A-MAS solution for WiMAX, the industrys first implementation of the full 802.16e profile requirements. The WiMAX profiles support both adaptive antenna system (AAS) and multipleinput/multiple-output (MIMO) architectures in baseline form. ArrayComms MAS implementation enhances baseline MIMO through the addition of essential interference mitigation. Generic MIMO systems provide link robustness and enhance point-to-point data rates by transmitting signals multiple times and/or transmitting multiple signals. Without active 120 of 141

Specifications: OS Support Windows 2000, Windows XP, Windows Me, Windows 98SE Package Contents Notebook Adapter, Setup CD with Manual, Quick Setup Guides, Warranty Statement Technical Specifications Standards Compliance Frequency Range Transmission Rate Security Access Mode Selectable Channels Communication Protocol 802.11g (Wireless LAN Standard) 802.11b (Wireless LAN Standard) 2.412 - 2.462 GHz 125* High-Speed Mode: 13, 20, 27, 40, 54, 80, 110, 125 Mbps 802.11g: 6, 9, 12, 18, 18, 24, 36, 48, 54 Mbps 802.11b: 1, 2, 5.5, 11 Mbps WPA-PSK (AES, TKIP), 802.1x Support (requires supplicant), 128/64-bit WEP Infrastructure Mode / Ad-Hoc Mode 11 Channels Direct Sequence Spread

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External Antenna Connector MC Card Connector Interface Dimensions Weight Operating Environment 32-Bit CardBus 2.2 x 0.5 x 4.8 in. (55 x 13 x 122 mm) 2.1 oz. (60 g) 0-55C, 20-80% (non-condensing)
Wireless-G MIMO Performance* Router & Access Point
o Features: Built-in Amplifier Improves Wireless Performance and Extends Range o 802.11g Wireless 125* High- Speed Mode Transfer Rates When Used with 125* High-Speed Mode Adapter (Turbo G) o Offers increased performance and range with all wireless or G clients. o Simple Web Browser Configuration o Supports WDS To Increase Coverage With Optional Repeater o External Switch To Instantly Change Between Wireless Router and Wireless Access Point o Easy Setup with AirStation One-Touch Secure System (AOSS) o Automatic Channel Support Selects Best Available Wireless Networking Channel o Supports WPA-PSK (TKIP, AES) and 128/64-bit WEP Security o Includes NAT and SPI Firewall and Intrusion Detector o Dynamic Packet Filtering o Built-in DHCP Server o Built-in 10/100 4-Port Auto-Sensing Switch Optimized High-Speed Routing, up to 5 Times Faster than Standard Routers o Great Value. Higher Performance than Standard 802.11g at Comparable Prices o RP-SMA to MC coupler required for use with the WLE-DA2, WLE-HG-NDR and WLEMYG antennas. Coupler not included. Smart Antennas in Fixed Wireless 128 of 141
o Works seamlessly with Nintendo DS The Wireless-G MIMO Performance* Router & Access Point combines the High Power wireless performance with Buffalos AirStation One-Touch Secure System (AOSS). Uniquely equipped with a built-in signal amplifier, the WHR-HP-G54 produces a true 60% increase in wireless transmit power over a standard 802.11g wireless router. WHR-HP-G54 extends the range of standard 802.11g client devices by up to 70% and improves overall performance by up to 50%. This Smart Router automatically detects and configures your Cable or DSL internet connection. Security features include WPA, WEP, Privacy Separator, Intrusion Detector, and SPI firewall. In addition to fast wireless performance, WHR-HP-G54 features a built-in external switch between wireless router and wireless access point modes. The combination of speed, security, and push-button setup of wireless connections and internet, makes the Buffalo AirStation G54 High Power Wireless Cable/DSL Smart Router the perfect choice for your wireless network. *This product uses a two antenna/single high power transmitter technology. It is not designed to anticipated 802.11n standards. Based on Buffalo Technology outdoor tests (see accompanying chart), this product outperforms two radio/three antenna MIMO technology beyond certain distances. Buffalo Technology testing also shows that this product equals or exceeds the performance of two radio/two antenna MIMO technology at all distances.