H.H. Hmimy

Southern Methodist University

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S.C. Gupta

Galgotias University

S.C. Gupta

Southern Methodist University

P. Chandrasekaran

A. Ahmedi

Ericsson (United States)

A. Triggs

Ericsson (United States)

Neeraj Mohan

Punjab Technical University

Mirza Golam Kibria

Huawei Technologies (Sweden)

Cooperative Institutions

Ericsson (United States)

Punjab Technical University

PSG INSTITUTE OF TECHNOLOGY AND APPLIED RESEARCH

Indian Institute of Science Education and Research Mohali

Indian Institute of Management Ahmedabad

Southern Methodist University

Tejas Networks (India)

Pompeu Fabra University

University of Alabama

Indian Institute of Technology Delhi

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Drive test based EDGE radio network performance evaluation

Neeraj Mohan P. Chandrasekaran H.H. Hmimy

In this paper, the performance of EDGE radio network is measured and evaluated considering different services applications namely FTP, HTTP, and MMS. Although today EDGE is a mature technology, it is under consistent evolution and enhancement. The focus of this paper is on the field-testing for EDGE R99. The tests are conducted in a GSM/EDGE network that carries GSM voice traffic and EDGE Packet Switched data services. The end-to-end performance evaluation methodology is briefly described with the focus on the radio network testing. The end-to-end key performance indicators (KPI) are defined for the different types of applications. Results from the field are presented for different applications at different radio conditions.

GSM

Network Performance

Packet radio

10.1109/vetecf.2005.1558223

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Performance of frequency-hopped NPCSMA for broad-band personal communication services (B-PCS) at millimeter waves in an urban mobile radio environment

IEEE Transactions on Vehicular Technology (1999)

H.H. Hmimy S.C. Gupta

A millimeter-wave (MMW) propagation model, based on multiray optical theory and the geometrical theory of diffraction (GTD), is used to statistically study the delay spread and coherence bandwidth (B/sub c/) for broad-band personal communication services (B-PCSs) in urban mobile radio environments. The results of the statistical model are compared with outdoor measurements near the street level with B/sub c/ varying over a range of frequencies (14-100 MHz). It is shown that the distribution of B/sub c/ depends on antenna heights, street layout, and frequency. The signal level statistics are evaluated and found to agree with the measurements. In general, these statistics are non-Rayleigh distributed. The additive thermal Gaussian noise (AGN) is calculated for such channels to evaluate the signal-to noise ratio (SNR). The performance of the medium-access control (MAC) sublayer is studied by first evaluating the probability of packet retransmission and then the performance of the FH-NPCSPMA protocol. The FH-NPCSMA protocol is the combination of frequency hopping spread spectrum (FH-SS) and nonpersistent carrier-sense multiple access (NPCSMA) that is proposed to improve the system throughput and average packet delay for both high traffic and multipath channels at MMW. The main advantage of the PH-NPCSMA protocol is to improve the performance over fading channels.

Coherence bandwidth

Frequency-hopping spread spectrum

Radio spectrum

Retransmission

Frequency band

10.1109/25.740064

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Channel estimation based on coded pilot for OFDM

H.H. Hmimy

The multipath fast frequency selective fading channel is estimated using coded pilot, based on DS-SS, for orthogonal frequency division multiplexing (CP-OFDM). The effect of the channel is equalized using channel inversion and channel estimation with maximum likelihood sequence estimation (CE-MLSE). The performance of unfaded coded pilot OFDM is derived for AWGN. The performance of channel inversion and CE-MLSE are simulated for multipath fast fading channels. The coded pilot estimation occurs at the same instant that the signal undergoes the fading effect which makes it suitable for fast fading channels.

Fading distribution

Pilot signal

10.1109/vetec.1997.605432

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Citations (13)

EDGE air-interface capacity analysis

A. Ahmedi A. Triggs H.H. Hmimy

The third generation evolution paths for GSM and TDMA include a common air-interface standard entitled Enhanced Data Rates for Global Evolution (EDGE). This paper discuss the EDGE air-interface capabilities, modes, and features. It examines the frequency reuse, and link throughput capabilities for the EDGE radio interface in a TDMA network. The upper bound on the base station transceiver's (BTS) link throughput is developed based on the available spectrum and frequency groups. A case study of the coverage area with 30 BTSs in an urban environment is studied and presented for different reuse patterns. The carrier to interference ratio is modeled for worst case 100% utilization and the link throughput is estimated for the coverage area and on the cell level.

Air interface

Interface (matter)

GSM

Transceiver

10.1109/ets.2000.916518

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Overlay of cellular CDMA on AMPS forward and reverse link analysis

IEEE Transactions on Vehicular Technology (1996)

H.H. Hmimy S.C. Gupta

The forward and reverse link capacities of code division multiple access (CDMA) and analog cellular system in North America (AMPS) are derived when they are overlaid. Formulas that describe the relationship between the number of CDMA and AMPS users for a given carrier to interference ratio (C/I) of each are presented. A nonlinear system that reduces the power of narrow-band interference is introduced. Simulation results are presented for one narrow-band interferer.

Cellular radio

10.1109/25.481820

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Citations (31)

Throughput-delay analysis of frequency hopped NPCSMA in outdoors cellular multipath fading and shadowing channels

H.H. Hmimy S.C. Gupta

In this paper, the probability of packet retransmission is evaluated for SFH-NCFSK in outdoor fading and shadowing channels for macrocell structure at 800/900 MHz. The channel throughput-delay analysis for NPCSMA is evaluated and simulated for outdoor Rayleigh fading and log-normal shadowing channels. The channel throughput-delay characteristics are degraded due to fading and shadowing. A new random multiple access protocol, which combines the advantages of frequency hopping spread spectrum (FH-SS) and carrier sense multiple access (CSMA), is introduced. The system throughput-delay characteristics are analytically derived in noiseless channels and in cellular channels. Monte Carlo simulation is used to verify the analytical results.

Macrocell

Retransmission

Shadow mapping

10.1109/vetec.1996.504052

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CDMA to DAMPS intersystem interference at 850 MHz

H.H. Hmimy Mirza Golam Kibria

This paper models and analyzes the interference on both uplink and downlink from CDMA to DAMPS systems when the two systems are operating in adjacent areas. The interference model uses the established DAMPS and CDMA system parameters from the standard to evaluate the CDMA inter-system interference (ISYSI) and to define the guard zone between the cells' borders.

Guard (computer science)

10.1109/vetec.1997.596385

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Citations (1)

Throughput-delay analysis of frequency hopped NPCSMA in indoors Rician fading cellular channels

H.H. Hmimy S.C. Gupta

The probability of packet retransmission is evaluated for SFH-NCFSK in indoor Rice fading channels for microcell structure at 800/900 MHz. The channel throughput-delay analysis for NPCSMA is evaluated and simulated for indoor Rician fading channels. The channel throughput-delay characteristics are degraded due to fading and shadowing. A new random multiple access protocol, which combines the advantages of frequency hopping spread spectrum (FH-SS) and carrier sense multiple access (CSMA), is introduced. The system throughput-delay characteristics are analytically derived in noiseless channels and in cellular channels. Monte Carlo simulation is used to verify the analytical results.

Rician fading

Microcell

Retransmission

10.1109/pccc.1996.493649

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Performance evaluation of SFH-SS transmission for outdoors personal communication services at millimeter-waves

H.H. Hmimy S.C. Gupta

A propagation model for PCS at MMW, based on multi-ray theory and geometrical theory of diffraction is introduced. The signal to noise ratio statistics are evaluated then the probability of packet re-transmission is found using the model output statistics.

Extremely high frequency

10.1109/vetec.1996.501499

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Citations (1)

Statistical model of delay spread and coherence bandwidth for wide-band PCS at millimeter-waves in an urban mobile radio environment

H.H. Hmimy S.C. Gupta

A MM wave propagation model, based on multi-ray optical theory and the geometrical theory of diffraction (GTD), is used to statistically study the delay spread and coherence bandwidth (B/sub c/) for wide-band personal communication services (PCS) in urban mobile radio environment. The statistical model results are compared with measurements and they agree that, for outdoors near street level, B/sub c/ is varying over a range of frequencies (14-100 MHz). It is shown that the B/sub c/ distribution depends on antenna heights, street layout, and frequency. The signal level statistics are evaluated which also agree with the measurements that, in general, the statistics are non-Rayleigh distributed.

Coherence bandwidth

Extremely high frequency

Rayleigh distribution

Radio spectrum

10.1109/icc.1996.541404

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Citations (4)