Peter J. Black

CDMA/HDR: a bandwidth efficient high speed wireless data service for nomadic users

This article presents an approach to providing very high-data-rate downstream Internet access by nomadic users within the current CDMA physical layer architecture. A means for considerably increasing the throughput by optimizing packet data protocols and by other network and coding techniques are presented and supported by simulations and laboratory measurements. The network architecture, based on Internet protocols adapted to the mobile environment, is described, followed by a discussion of economic considerations in comparison to cable and DSL services.

CDMA2000 1/spl times/EV-DO revision a: a physical layer and MAC layer overview

This article presents key enhancements to CDMA2000 1/spl times/EV-DO systems embodied in 1/spl times/EV-DO Revision A. These enhancements provide significant gains in spectral efficiency and substantial improvements in QoS support relative to 1/spl times/EV-DO Revision 0. In particular, 1/spl times/EV-DO Revision A approximately doubles the uplink spectral efficiency and doubles the number of terminals with delay-sensitive applications that can be simultaneously supported on the system. It provides substantial reduction in latencies (approximately 50 percent) during both connection setup and the connected state. It offers comprehensive network control over terminal and application performance to enable the desired trade-offs between capacity and latency/ fairness, thereby providing full QoS support and enhanced user experience. It also provides coverage improvement (approximately 1.5 dB) relative to 1/spl times/EV-DO Revision 0. This enables operators to offer services such as VoIP, video telephony, mobile network gaming, push-to-talk, Web browsing, file transfer, and video on demand to a larger number of simultaneous users. The 1/spl times/EV-DO Revision A network can provide downlink sector capacity of 1500 kb/s and uplink capacity of 500 kb/s (two-way receive diversity) or 1200 kb/s (four-way receive diversity) with 16 active users per sector, using just 1.25 MHz of the spectrum.

Evolution of cdma2000 cellular networks: multicarrier EV-DO

The evolution of cdma2000 1xEV-DO systems to multicarrier EV-DO (supported by 1xEV-DO Revision B) is discussed in this article. Multicarrier EV-DO offers a backward-compatible upgrade to leverage existing 1xEV-DO networks and terminals. It allows a software upgrade to multicarrier EV-DO using 1xEV-DO Revision A base station hardware. Multicarrier operation achieves higher efficiencies relative to single-carrier by exploiting channel frequency selectivity, improved transmit efficiencies on the reverse link, and adaptive load balancing across carriers. Multicarrier EV-DO enables very high-speed download, high-resolution video telephony, and improved user experience with concurrent applications. The sources of higher efficiency are discussed in detail in this article. It also enables hybrid frequency reuse deployment scenarios that enable spectrally efficient operation and significant improvement in edge coverage performance with hardware-efficient implementations. The evolved wider bandwidth systems (up to 20 MHz) based on multicarrier EV-DO offer operators a cost-effective solution that competes favorably with other technologies.

VoIP over cdma2000 1xEV-DO revision A

In this article we analyze performance of VoIP services over 1xEVDO-Revision A (DO-Rev A) networks and show that high-quality VoIP with unconstrained mobility and high capacity can be achieved. Together with quality of service (QoS) requirements, we emphasize practical issues such as mobility, degradation of feedback-channel quality, and packet overheads. Novel techniques are presented for voice processing such as smart blanking and adaptive dejitter playback buffer with time warping. These techniques help to meet QoS constraints to achieve a circuit-like voice quality while improving overall capacity. Detailed end-to-end simulations are presented and system capacity is analyzed under the QoS and system stability constraints. We claim that DO-Rev A can provide VoIP capacity comparable to circuit-switched cellular CDMA technologies (e.g., IS-2000) and simultaneously carry significant amount of other types of traffic such as non-delay sensitive applications and downlink multicast.

Link budget of cdma2000 1xEV-DO wireless Internet access system

This paper presents the analysis and simulation results for a 1xEV-DO link budget. The traditional fixed rate CDMA link budget calculation has been extended to include link adaptation and multi-user diversity gains. The main conclusion is that 1xEV-DO provides a link budget advantage over IS-95-A of approximately 10 dB on the forward link and 1.5 dB on the reverse link.

Interference Cancellation Techniques for CDMA2000 1x Reverse Link

Interference cancellation (IC) techniques yielding significant capacity gains are presented in this paper for CDMA2000 1x base station receiver. In addition to performance gain from conventional IC, hybrid ARQ gain is achieved effectively without interlaced transmission or feedback on the forward link (FL). A new definition of CDMA capacity, based on equivalent load, is introduced to allow a fair comparison of capacity with and without IC. Results from detailed simulations show that capacity gain for a typical commercial network will be between twofold and threefold, depending on spatial load distribution in the network. This capacity gain is achieved without any increase in voice latency or degradation to voice quality. It also does not require changes to the air interface or any handset replacement. The techniques proposed in this paper are applicable to base station receivers of other CDMA systems such as UMTS.

cdma2000 Highly Detectable Pilot

Research and development on mobile phone positioning technologies are gaining momentum due to the potential in location based services. Mobile location is estimated based on measurements from satellites and terrestrial base stations. Satellite measurements often available in rural and suburban areas are less or not available in dense urban and indoor areas. Thus, base station measurements play an important role in mobile positioning. In this paper, we present the highly detectable pilot (HDP) that is being standardized in 3GPP2 for cdma2000 1xEV-DO. HDP allows mobile to detect significantly more base stations, and thus provides much better accuracy in location estimate.

cdma2000 1/spl times/EV-DO forward link throughput sensitivity to diversity antenna correlation

This paper addresses the effects of the fade correlation between the receiver antennas of an access terminal (AT) on the forward link sector capacity of a cdma2000 1/spl times/EV-DO system. Traditionally, high fade correlation has been considered to be a significant source of capacity degradation for fixed rate wireless data/voice modems due to the lack of diversity and hence the increased variance of the received signal power which results in an increased fade margin or power control set point. The 1/spl times/EV-DO system, due to its advanced link adaptation, variable rate control, and multiuser diversity mechanisms, possesses inherent robustness towards such a lack of diversity. This point is demonstrated in this paper by network level simulations as well as by field data.

cdma2000 1x Rev. E Forward Link Voice Capacity

The forward link capacity of a cdma2000 lx system is power limited. Therefore, average data rate (ADR), link efficiency, and receiver signal-to-noise ratio (SNR) are the key factors for capacity improvement. In this paper, we introduce the new features of the forward fundamental channel (F-FCH) with radio configuration (RC) 11 for 1x Revision E that is being standardized at the Third Generation Partnership Project 2 (3GPP2) and advanced receivers for mobile stations (MS), targeted at these key factors. Simulations show that the new RC together with interference cancellation and a new voice codec more than doubles the forward link capacity of existing 1x systems, and more than triples the capacity with dual receive antennas. The capacity gain is achieved without any increase in voice latency or any degradation in voice quality.