This contribution includes clarification on the current extended DL/UL IEs. Purpose Review and ad... more This contribution includes clarification on the current extended DL/UL IEs. Purpose Review and adopt suggested change into P802.16e/D5a-2004 Notice This document has been prepared to assist IEEE 802.16. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.
All of the specification material within contribution 373 is included in this contribution (i.e.,... more All of the specification material within contribution 373 is included in this contribution (i.e., 373 is a subset of this contribution). Purpose Complete the LDPC specification text. Notice This document has been prepared to assist IEEE 802.16. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to
and Computer Engineering OFDM is mainly designed to combat the effect of multipath reception, by ... more and Computer Engineering OFDM is mainly designed to combat the effect of multipath reception, by dividing the wide-band frequency selective fading channel into many narrow-band flat subchannels. OFDM offers flexibility in adaptation to time-varying channel condition by adopting the parameters at each subcarrier accurately. The purpose of this work is to use this flexibility and study the OFDM systems with power control, multiple transmit and receive antennas, the problem of Peak to Average Power Ratio (PAPR), and the effect of OFDM in providing QoS. An OFDM uplink multiuser wireless network, combined with power control and receive beamforming is proposed to achieve the desired SINR at each OFDM subchannel. Consequently, better overall BER with the same total power is achieved. To reduce the receiver complexity, joint time-domain beamforming and power control is also provided. The proposed algorithm is also extended to COFDM. We use distributed schemes to maximize the maximum achievable data rate for each receiver in a multiuser downlink transmission using MIMO/OFDM, by finding the optimal transmit and receive weight vectors. We propose iterative algorithms to distribute the limited power (per carrier or per user) to multiple streams and multiple antennas in order to maximize the allocated rate per user. The game theoretic analogy of the problem is stated and the convergence of the algorithms are discussed. To increase the information rate of low PAPR OFDM codes, we propose two frameworks. Super Golay sequences constructed from 16-QAM constellation having PAPR bounded up to 3dB are defined, and constructed by recursive structures. Cyclic-Golay codes are also proposed and constructed by a framework that can be used to obtain the cyclic shift of any code represented by Boolean algebraic functions. These codes are in general a subset of generalized Reed-Muller codes, and have lower error correction capabilities compared to Golay sequences. An extension of the majority logic Reed algorithm for decoding Reed-Muller codes of any order is provided. To reduce decoding complexity, recursive maximumlikelihood decoding schemes are also provided, and the complexity of these algorithms are
IEEE International Symposium on Information Theory, 2003. Proceedings., 2003
T h i s paper addresses the problem of space-frequency code design for broadband multia n t e n n... more T h i s paper addresses the problem of space-frequency code design for broadband multia n t e n n a OFDM systems. We show that space-time codes achieving full diversity in quasi-static flat fading environment can be used to construct space-frequency
— In this paper, the cyclic shifts of low Peak to Average Power Ratio (PAPR) codes used in OFDM t... more — In this paper, the cyclic shifts of low Peak to Average Power Ratio (PAPR) codes used in OFDM transmission is proposed. They comprise a superclass of Golay Complementary Codes (GCC) with the same level of PAPR (viewed by the discrete OFDM symbols). These codes achieve higher information rate with the expense of lower error correction capabilities. We have proposed a framework for constructing these codes out of GCC. The framework can be applied to obtain the cyclic shift of any code represented by Boolean algebraic functions. An efficient transmission scheme is proposed such that the coding scheme can be switched between the Golay and cyclic Golay codes, based on a feedback from the receiver to perform a better tradeoff between the coding rate, and Bit Error Rate (BER). I.
New Directions in Wireless Communications Research, 2009
... Reference Point R2 consists of accounting, authentication, authorization, and ... the interfa... more ... Reference Point R2 consists of accounting, authentication, authorization, and ... the interfaces R1, R2, R3, and R4 are open (standardized) and must be interoperable, while R6 could ... duration is a trade-off between the delay and latency performances (such as handoff delay) and ...
This contribution includes clarification on the current extended DL/UL IEs. Purpose Review and ad... more This contribution includes clarification on the current extended DL/UL IEs. Purpose Review and adopt suggested change into P802.16e/D5a-2004 Notice This document has been prepared to assist IEEE 802.16. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.
All of the specification material within contribution 373 is included in this contribution (i.e.,... more All of the specification material within contribution 373 is included in this contribution (i.e., 373 is a subset of this contribution). Purpose Complete the LDPC specification text. Notice This document has been prepared to assist IEEE 802.16. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to
and Computer Engineering OFDM is mainly designed to combat the effect of multipath reception, by ... more and Computer Engineering OFDM is mainly designed to combat the effect of multipath reception, by dividing the wide-band frequency selective fading channel into many narrow-band flat subchannels. OFDM offers flexibility in adaptation to time-varying channel condition by adopting the parameters at each subcarrier accurately. The purpose of this work is to use this flexibility and study the OFDM systems with power control, multiple transmit and receive antennas, the problem of Peak to Average Power Ratio (PAPR), and the effect of OFDM in providing QoS. An OFDM uplink multiuser wireless network, combined with power control and receive beamforming is proposed to achieve the desired SINR at each OFDM subchannel. Consequently, better overall BER with the same total power is achieved. To reduce the receiver complexity, joint time-domain beamforming and power control is also provided. The proposed algorithm is also extended to COFDM. We use distributed schemes to maximize the maximum achievable data rate for each receiver in a multiuser downlink transmission using MIMO/OFDM, by finding the optimal transmit and receive weight vectors. We propose iterative algorithms to distribute the limited power (per carrier or per user) to multiple streams and multiple antennas in order to maximize the allocated rate per user. The game theoretic analogy of the problem is stated and the convergence of the algorithms are discussed. To increase the information rate of low PAPR OFDM codes, we propose two frameworks. Super Golay sequences constructed from 16-QAM constellation having PAPR bounded up to 3dB are defined, and constructed by recursive structures. Cyclic-Golay codes are also proposed and constructed by a framework that can be used to obtain the cyclic shift of any code represented by Boolean algebraic functions. These codes are in general a subset of generalized Reed-Muller codes, and have lower error correction capabilities compared to Golay sequences. An extension of the majority logic Reed algorithm for decoding Reed-Muller codes of any order is provided. To reduce decoding complexity, recursive maximumlikelihood decoding schemes are also provided, and the complexity of these algorithms are
IEEE International Symposium on Information Theory, 2003. Proceedings., 2003
T h i s paper addresses the problem of space-frequency code design for broadband multia n t e n n... more T h i s paper addresses the problem of space-frequency code design for broadband multia n t e n n a OFDM systems. We show that space-time codes achieving full diversity in quasi-static flat fading environment can be used to construct space-frequency
— In this paper, the cyclic shifts of low Peak to Average Power Ratio (PAPR) codes used in OFDM t... more — In this paper, the cyclic shifts of low Peak to Average Power Ratio (PAPR) codes used in OFDM transmission is proposed. They comprise a superclass of Golay Complementary Codes (GCC) with the same level of PAPR (viewed by the discrete OFDM symbols). These codes achieve higher information rate with the expense of lower error correction capabilities. We have proposed a framework for constructing these codes out of GCC. The framework can be applied to obtain the cyclic shift of any code represented by Boolean algebraic functions. An efficient transmission scheme is proposed such that the coding scheme can be switched between the Golay and cyclic Golay codes, based on a feedback from the receiver to perform a better tradeoff between the coding rate, and Bit Error Rate (BER). I.
New Directions in Wireless Communications Research, 2009
... Reference Point R2 consists of accounting, authentication, authorization, and ... the interfa... more ... Reference Point R2 consists of accounting, authentication, authorization, and ... the interfaces R1, R2, R3, and R4 are open (standardized) and must be interoperable, while R6 could ... duration is a trade-off between the delay and latency performances (such as handoff delay) and ...
Uploads
Papers by Masoud Olfat