In this paper, dual-wavelength laser emission of an erbium-doped fiber laser (EDFL) with a tunabl... more In this paper, dual-wavelength laser emission of an erbium-doped fiber laser (EDFL) with a tunable distinct wavelength selection of the simultaneously produced laser lines was achieved by applying a parallel comb filter configuration based on the optical Vernier effect. The intracavity inserted proposed comb filter consists of two parallel branches to generate the Vernier effect. Each branch is an in-line Mach–Zehnder interferometer (MZI) filter, which is composed of a polarization-maintaining fiber fusion spliced between single-mode fibers with sphere shapes at both ends. The tunability of the selected laser wavelength was realized by submerging the proposed filter in different sodium chloride/water mixtures. The proposed comb filter-based Vernier effect was used to independently achieve the selection of the dual-wavelength EDFL lines and for refractive index (RI) sensing applications. The in-line MZI1 and MZI2 structures show a wavelength shift sensitivity to RI variations of −88 and 79 nm/RIU, respectively. Our proposed MZI structure presents a reliable, straightforward, and low-cost spectral comb filter for separate tunable dual-wavelength laser generation in the c-band region. Furthermore, the proposed filter structure-based Vernier effect presents a new perspective and method in the RI sensing application.
International journal of physiology, nutrition and physical education, 2023
One of the issues that experts in the field of sports training face, especially in training the g... more One of the issues that experts in the field of sports training face, especially in training the game of basketball on wheelchairs, is that the training process takes place by relying on training the healthy part of the body of the handicapped, such as the torso and arms, without paying attention to the other parts of his body, and this is one of the scientific problems related to the applied side, which would Delaying the development of achievement for these players and herein lies the research problem. Where the research aims to use the (TENS) device on basketball players on wheelchairs and to identify the extent of the impact of this device on the development of some offensive skills in basketball for the disabled on wheelchairs. The researchers used the experimental approach, as it is one of the most widely used scientific research methods in the field of sports, and they concluded that the use of the (TENS) device has contributed to the development of their offensive skill capabilities for wheelchair basketball players, indicating that there are statistically significant discrepancies between the research results, with the experimental group benefiting. The researchers recommend the physical training and the development of the special technical aspects should be based on the use of electrical muscle stimulation and the development of special strength is necessary in the competition, in addition to controlling the nervous adaptation, which includes a high value of exercises and increasing the speed of movement during the game.
The basketball game is one of the activities of the group games, which have been dealt with by ma... more The basketball game is one of the activities of the group games, which have been dealt with by many studies and researches to obtain the best achievement. The importance of the research lies in how to introduce vacuum exercises and develop biokinetic abilities and capacities by means of modern scientific training. The current research aims to identify the relationship between some vacuum exercises and biokinetic capabilities with the ability to develop various elements of physical and skillful fitness such as deception and overtaking the opponent player, since most of the research is looking specifically for a specific physical ability or skill only without paying attention to motor performance in general in terms of continuing to maintain outstanding good performance and stamina throughout the match. Thus, this research imposed a statistically significant correlation between vacuum exercises and biokinetic abilities in terms of the possibility of developing elements of physical fitness that may not be at a good level for this sample in particular, and the possibility of endurance and maintaining the level of performance throughout the match period in the game of basketball at a good level. The researchers used the experimental method. As for the research sample, the Baghdad Al-Karkh breeding team / 3 basketball players were (12) players, and the researchers conducted tests for some biokinetic abilities and vacuum exercises, and the researchers used the program (spss) to treat the statistical data. The researchers concluded that there are correlations between some vacuum exercises and biokinetic abilities, and between the physical fitness of female basketball players. Vacuum exercises have a significant impact on basketball players in terms of increasing the lung capacity and strengthening the abdominal muscles. Biomotor abilities have a positive effect on the level of performance. The researchers recommend the necessity of applying these tests in studying the relationship with another type and with other age groups.
A single carrier transmission scheme is presented for the frequency selective multiuser (MU) mult... more A single carrier transmission scheme is presented for the frequency selective multiuser (MU) multiple-input singleoutput (MISO) Gaussian Broadcast Channel (GBC) with a base station (BS) having M antennas and K single antenna users. The proposed transmission scheme has low complexity and for M ≫ K it is shown to achieve near optimal sum-rate performance at low transmit power to receiver noise power ratio. Additionally, the proposed transmission scheme results in an equalization-free receiver and does not require any MU resource allocation and associated control signaling overhead. Also, the sum-rate achieved by the proposed transmission scheme is shown to be independent of the channel power delay profile (PDP). In terms of power efficiency, the proposed transmission scheme also exhibits an O(M) array power gain. Simulations are used to confirm analytical observations.
In this paper, we study the impact of frequency-selectivity on the gap between the required per-u... more In this paper, we study the impact of frequency-selectivity on the gap between the required per-user transmit power in the residual CFO scenario (i.e. after CFO estimation/compensation at the base-station (BS) from [6]) and that in the ideal/zero CFO scenario, for a fixed per-user information rate, in singlecarrier massive MU-MIMO uplink systems with the TR-MRC receiver. Information theoretic analysis reveals that this gap decreases with increasing frequency-selectivity of the channel. Also, in the residual CFO scenario, an O(√ M) array gain is still achievable (M is the number of BS antennas) in frequencyselective channels with imperfect channel estimates. Index Terms Massive MIMO, carrier frequency offset (CFO), frequency selective channel, Time-reversal maximum ratio combining (TR-MRC), single-carrier.
We consider the problem of accurate channel estimation for OTFS based systems with few transmit/r... more We consider the problem of accurate channel estimation for OTFS based systems with few transmit/receive antennas, where additional sparsity due to large number of antennas is not a possibility. For such systems the sparsity of the effective delay-Doppler (DD) domain channel is adversely affected in the presence of channel path delay and Doppler shifts which are noninteger multiples of the delay and Doppler domain resolution. The sparsity is also adversely affected when practical transmit and receive pulses are used. In this paper we propose a Modified Maximum Likelihood Channel Estimation (M-MLE) method for OTFS based systems which exploits the fine delay and Doppler domain resolution of the OTFS modulated signal to decouple the joint estimation of the channel parameters (i.e., channel gain, delay and Doppler shift) of all channel paths into separate estimation of the channel parameters for each path. We further observe that with fine delay and Doppler domain resolution, the received DD domain signal along a particular channel path can be written as a product of a delay domain term and a Doppler domain term where the delay domain term is primarily dependent on the delay of this path and the Doppler domain term is primarily dependent on the Doppler shift of this path. This allows us to propose another method termed as the twostep method (TSE), where the joint two-dimensional estimation of the delay and Doppler shift of a particular path in the M-MLE method is further decoupled into two separate one-dimensional estimation for the delay and for the Doppler shift of that path. Simulations reveal that the proposed methods (M-MLE and TSE) achieve better channel estimation accuracy at lower complexity when compared to other known methods for accurate OTFS channel estimation.
The author has also granted permission to the University to keep or make a digital copy for simil... more The author has also granted permission to the University to keep or make a digital copy for similar use and for the purpose of preservation of the work digitally. Multiple copying of this work for scholarly purposes may be granted by either the author, the Registrar or the Dean only. Copying for financial gain shall only be allowed with the author's express permission.
In this paper 1 , we propose and analyze a novel idea of performing interference cancellation (IC... more In this paper 1 , we propose and analyze a novel idea of performing interference cancellation (IC) in a distributed/cooperative manner, with a motivation to provide multiuser detection (MUD) benefit to nodes that have only a single user detection capability. In the proposed distributed interference cancellation (DIC) scheme, during Phase-1 of transmission, an MUD capable cooperating relay node estimates all the sender nodes' bits through multistage interference cancellation. These estimated bits are then sent by the relay node on orthogonal tones in Phase-2 of transmission. The destination nodes receive these bit estimates and use them for interference estimation/cancellation, thus achieving IC benefit in a distributed manner. For this DIC scheme, we analytically derive an exact expression for the bit error rate (BER) in a basic five-node network (two source-destination node pairs and a cooperating relay node) on AWGN channels. Analytical BER results are shown to match with simulation results. For more general system scenarios, including more than two source-destination pairs and fading channels without and with space-time coding, we present simulation results to establish the potential for improved performance in the proposed distributed approach to interference cancellation. We also present a linear version of the proposed DIC.
IEEE Transactions on Wireless Communications, 2012
In this paper, we address the design of codes which achieve modulation diversity in block fading ... more In this paper, we address the design of codes which achieve modulation diversity in block fading singleinput single-output (SISO) channels with signal quantization at receiver and low-complexity decoding. With an unquantized receiver, coding based on algebraic rotations is known to achieve modulation coding diversity. On the other hand, with a quantized receiver, algebraic rotations may not guarantee diversity. Through analysis, we propose specific rotations which result in the codewords having equidistant component-wise projections. We show that the proposed coding scheme achieves maximum modulation diversity with a low-complexity minimum distance decoder and perfect channel knowledge. Relaxing the perfect channel knowledge assumption we propose a novel training/estimation and receiver control technique to estimate the channel. We show that our coding/training/estimation scheme and minimum distance decoding achieve an error probability performance similar to that achieved with perfect channel knowledge.
This book takes a solid step toward a systematic analysis of the implications of microfinance for... more This book takes a solid step toward a systematic analysis of the implications of microfinance for the role and regulation of capital markets. The authors address integration of capital markets with microfinance, technological innovations such as the use of mobile phone technology, the consequences of women’s access to micro-loan borrowings, and the regulatory challenges and opportunities emerging as the landscape of microfinance dramatically evolves.
Infection in the urine tract is more dominate as a medical condition around the world in the hosp... more Infection in the urine tract is more dominate as a medical condition around the world in the hospital and society, especially from young women and pregnant women. The reason for disease the first is uropathogenicEscherichia coli, which has several agents that help in the development that disease in addition to its the capability to stick on a host epithelial cell in urine tract with an assembly the biofilm, which is the most important factor for the disease. Therefore, a vaccine was made for these local isolates to avoid recurrent urinary tract infection and to obtain protective immunity by a laboratory mouse model. After isolation and diagnosis of 90 positive isolates using chrome agardiagnostic from women with urinary tract infection from hospitals in middle Iraq to Wasit province for the period from Jan. 2019 to Apr. 2019. All isolates were tested to detect virulence factors. One isolate was chosen for the determine LD50, immunization and vaccine model, then to estimate the antibody (IgG) level during immunization in the serum of mice at 6 weeks. Results proved that isolates showed positive (71.11%) biofilm, (23.33%) α-heamolysin, (31.11%) serum resistance, and (41.11%) MRHA and (5.55%) MSHA , while LD50=(1*10 10).There are highly significant differences when using isolate in the level of IgG reaches the high peak ranged (749.1 ±20.4) in 6 weeks as compared with control. The results showed that the local vaccine for this isolation provided preventive protection by inducing a protective immune response in mice to protect against infection.
In this paper, we study the achievable rate region of two-user Gaussian broadcast channel (GBC) w... more In this paper, we study the achievable rate region of two-user Gaussian broadcast channel (GBC) when the messages to be transmitted to both the users take values from finite signal sets and the received signal is quantized at both the users. We refer to this channel as quantized broadcast channel (QBC). We first observe that the capacity region defined for a GBC does not carry over as such to QBC. Also, we show that the optimal decoding scheme for GBC (i.e., high SNR user doing successive decoding and low SNR user decoding its message alone) is not optimal for QBC. We then propose an achievable rate region for QBC based on two different schemes. We present achievable rate region results for the case of uniform quantization at the receivers. We find that rotation of one of the user's input alphabet with respect to the other user's alphabet marginally enlarges the achievable rate region of QBC when almost equal powers are allotted to both the users.
In this paper we consider Millimeter wave (mmWave) Massive MIMO systems where a large antenna arr... more In this paper we consider Millimeter wave (mmWave) Massive MIMO systems where a large antenna array at the base station (BS) serves a few scheduled terminals. The high dimensional null space of the channel matrix to the scheduled terminals is utilized to broadcast system information to the non-scheduled terminals on the same time-frequency resource. Our analysis reveals the interesting result that with a sufficiently large antenna array this non-orthogonal broadcast strategy requires significantly less total transmit power when compared to the traditional orthogonal strategy where a fraction of the total resource is reserved for broadcast of system information.
We consider the impact of transceiver power consumption on the energy efficiency (EE) of the Zero... more We consider the impact of transceiver power consumption on the energy efficiency (EE) of the Zero Forcing (ZF) detector in the uplink of massive MIMO systems, where a base station (BS) with M antennas communicates coherently with K single antenna user terminals (UTs). We consider the problem of maximizing the EE with respect to (M, K) for a fixed sum spectral efficiency. Through analysis we study the impact of system parameters on the optimal EE. System parameters consists of the average channel gain to the users and the power consumption parameters (PCPs) (e.g., power consumed by each RF antenna/receiver at BS). When the average user channel gain is high or else the BS/UT design is power inefficient, our analysis reveals that it is optimal to have a few BS antennas and a single user, i.e., non-massive MIMO regime. Similarly, when the channel gain is small or else the BS/UT design is power efficient, it is optimal of have a larger (M, K), i.e., massive MIMO regime. Tight analytical bounds on the optimal EE are proposed for both these regimes. The impact of the system parameters on the optimal EE is studied and several interesting insights are drawn.
We consider Gaussian multiple-input multipleoutput (MIMO) channels with discrete input alphabets.... more We consider Gaussian multiple-input multipleoutput (MIMO) channels with discrete input alphabets. We propose a non-diagonal precoder based on X-Codes in [1] to increase the mutual information. The MIMO channel is transformed into a set of parallel subchannels using Singular Value Decomposition (SVD) and X-codes are then used to pair the subchannels. X-Codes are fully characterized by the pairings and the 2 × 2 real rotation matrices for each pair (parameterized with a single angle). This precoding structure enables to express the total mutual information as a sum of the mutual information of all the pairs. The problem of finding the optimal precoder with the above structure, which maximizes the total mutual information, is equivalent to i) optimizing the rotation angle and the power allocation within each pair and ii) finding the optimal pairing and power allocation among the pairs. It is shown that the mutual information achieved with the proposed pairing scheme is very close to that achieved with the optimal precoder by Cruz et al., and significantly better than mercury/waterfilling strategy by Lozano et al.. Our approach greatly simplifies both the precoder optimization and the detection complexity, making it suitable for practical applications.
We consider a point-to-point mm-wave massive multiple-input multiple-output hybrid beamforming sy... more We consider a point-to-point mm-wave massive multiple-input multiple-output hybrid beamforming system where the transmitter is impaired with in-phase and quadrature-phase imbalance (IQI). We propose a novel channel estimation and IQI parameter estimation algorithm which first estimates the true sparse channel parameters using which it then estimates the IQI parameters. We show that the transmitter IQI limits the spectral efficiency of hybrid beamforming systems at high signal-to-noise ratio irrespective of the choice of hybrid precoder/combiner. We also propose a novel IQI symbol-level pre-compensation scheme at the transmitter which modifies the input symbol vector to the transmit radio frequency (RF) chains in such a way that the symbol vector received at the output of the RF chains is free from any IQI. Analysis and simulations confirm the effectiveness of the proposed IQI pre-compensation technique.
In this paper, dual-wavelength laser emission of an erbium-doped fiber laser (EDFL) with a tunabl... more In this paper, dual-wavelength laser emission of an erbium-doped fiber laser (EDFL) with a tunable distinct wavelength selection of the simultaneously produced laser lines was achieved by applying a parallel comb filter configuration based on the optical Vernier effect. The intracavity inserted proposed comb filter consists of two parallel branches to generate the Vernier effect. Each branch is an in-line Mach–Zehnder interferometer (MZI) filter, which is composed of a polarization-maintaining fiber fusion spliced between single-mode fibers with sphere shapes at both ends. The tunability of the selected laser wavelength was realized by submerging the proposed filter in different sodium chloride/water mixtures. The proposed comb filter-based Vernier effect was used to independently achieve the selection of the dual-wavelength EDFL lines and for refractive index (RI) sensing applications. The in-line MZI1 and MZI2 structures show a wavelength shift sensitivity to RI variations of −88 and 79 nm/RIU, respectively. Our proposed MZI structure presents a reliable, straightforward, and low-cost spectral comb filter for separate tunable dual-wavelength laser generation in the c-band region. Furthermore, the proposed filter structure-based Vernier effect presents a new perspective and method in the RI sensing application.
International journal of physiology, nutrition and physical education, 2023
One of the issues that experts in the field of sports training face, especially in training the g... more One of the issues that experts in the field of sports training face, especially in training the game of basketball on wheelchairs, is that the training process takes place by relying on training the healthy part of the body of the handicapped, such as the torso and arms, without paying attention to the other parts of his body, and this is one of the scientific problems related to the applied side, which would Delaying the development of achievement for these players and herein lies the research problem. Where the research aims to use the (TENS) device on basketball players on wheelchairs and to identify the extent of the impact of this device on the development of some offensive skills in basketball for the disabled on wheelchairs. The researchers used the experimental approach, as it is one of the most widely used scientific research methods in the field of sports, and they concluded that the use of the (TENS) device has contributed to the development of their offensive skill capabilities for wheelchair basketball players, indicating that there are statistically significant discrepancies between the research results, with the experimental group benefiting. The researchers recommend the physical training and the development of the special technical aspects should be based on the use of electrical muscle stimulation and the development of special strength is necessary in the competition, in addition to controlling the nervous adaptation, which includes a high value of exercises and increasing the speed of movement during the game.
The basketball game is one of the activities of the group games, which have been dealt with by ma... more The basketball game is one of the activities of the group games, which have been dealt with by many studies and researches to obtain the best achievement. The importance of the research lies in how to introduce vacuum exercises and develop biokinetic abilities and capacities by means of modern scientific training. The current research aims to identify the relationship between some vacuum exercises and biokinetic capabilities with the ability to develop various elements of physical and skillful fitness such as deception and overtaking the opponent player, since most of the research is looking specifically for a specific physical ability or skill only without paying attention to motor performance in general in terms of continuing to maintain outstanding good performance and stamina throughout the match. Thus, this research imposed a statistically significant correlation between vacuum exercises and biokinetic abilities in terms of the possibility of developing elements of physical fitness that may not be at a good level for this sample in particular, and the possibility of endurance and maintaining the level of performance throughout the match period in the game of basketball at a good level. The researchers used the experimental method. As for the research sample, the Baghdad Al-Karkh breeding team / 3 basketball players were (12) players, and the researchers conducted tests for some biokinetic abilities and vacuum exercises, and the researchers used the program (spss) to treat the statistical data. The researchers concluded that there are correlations between some vacuum exercises and biokinetic abilities, and between the physical fitness of female basketball players. Vacuum exercises have a significant impact on basketball players in terms of increasing the lung capacity and strengthening the abdominal muscles. Biomotor abilities have a positive effect on the level of performance. The researchers recommend the necessity of applying these tests in studying the relationship with another type and with other age groups.
A single carrier transmission scheme is presented for the frequency selective multiuser (MU) mult... more A single carrier transmission scheme is presented for the frequency selective multiuser (MU) multiple-input singleoutput (MISO) Gaussian Broadcast Channel (GBC) with a base station (BS) having M antennas and K single antenna users. The proposed transmission scheme has low complexity and for M ≫ K it is shown to achieve near optimal sum-rate performance at low transmit power to receiver noise power ratio. Additionally, the proposed transmission scheme results in an equalization-free receiver and does not require any MU resource allocation and associated control signaling overhead. Also, the sum-rate achieved by the proposed transmission scheme is shown to be independent of the channel power delay profile (PDP). In terms of power efficiency, the proposed transmission scheme also exhibits an O(M) array power gain. Simulations are used to confirm analytical observations.
In this paper, we study the impact of frequency-selectivity on the gap between the required per-u... more In this paper, we study the impact of frequency-selectivity on the gap between the required per-user transmit power in the residual CFO scenario (i.e. after CFO estimation/compensation at the base-station (BS) from [6]) and that in the ideal/zero CFO scenario, for a fixed per-user information rate, in singlecarrier massive MU-MIMO uplink systems with the TR-MRC receiver. Information theoretic analysis reveals that this gap decreases with increasing frequency-selectivity of the channel. Also, in the residual CFO scenario, an O(√ M) array gain is still achievable (M is the number of BS antennas) in frequencyselective channels with imperfect channel estimates. Index Terms Massive MIMO, carrier frequency offset (CFO), frequency selective channel, Time-reversal maximum ratio combining (TR-MRC), single-carrier.
We consider the problem of accurate channel estimation for OTFS based systems with few transmit/r... more We consider the problem of accurate channel estimation for OTFS based systems with few transmit/receive antennas, where additional sparsity due to large number of antennas is not a possibility. For such systems the sparsity of the effective delay-Doppler (DD) domain channel is adversely affected in the presence of channel path delay and Doppler shifts which are noninteger multiples of the delay and Doppler domain resolution. The sparsity is also adversely affected when practical transmit and receive pulses are used. In this paper we propose a Modified Maximum Likelihood Channel Estimation (M-MLE) method for OTFS based systems which exploits the fine delay and Doppler domain resolution of the OTFS modulated signal to decouple the joint estimation of the channel parameters (i.e., channel gain, delay and Doppler shift) of all channel paths into separate estimation of the channel parameters for each path. We further observe that with fine delay and Doppler domain resolution, the received DD domain signal along a particular channel path can be written as a product of a delay domain term and a Doppler domain term where the delay domain term is primarily dependent on the delay of this path and the Doppler domain term is primarily dependent on the Doppler shift of this path. This allows us to propose another method termed as the twostep method (TSE), where the joint two-dimensional estimation of the delay and Doppler shift of a particular path in the M-MLE method is further decoupled into two separate one-dimensional estimation for the delay and for the Doppler shift of that path. Simulations reveal that the proposed methods (M-MLE and TSE) achieve better channel estimation accuracy at lower complexity when compared to other known methods for accurate OTFS channel estimation.
The author has also granted permission to the University to keep or make a digital copy for simil... more The author has also granted permission to the University to keep or make a digital copy for similar use and for the purpose of preservation of the work digitally. Multiple copying of this work for scholarly purposes may be granted by either the author, the Registrar or the Dean only. Copying for financial gain shall only be allowed with the author's express permission.
In this paper 1 , we propose and analyze a novel idea of performing interference cancellation (IC... more In this paper 1 , we propose and analyze a novel idea of performing interference cancellation (IC) in a distributed/cooperative manner, with a motivation to provide multiuser detection (MUD) benefit to nodes that have only a single user detection capability. In the proposed distributed interference cancellation (DIC) scheme, during Phase-1 of transmission, an MUD capable cooperating relay node estimates all the sender nodes' bits through multistage interference cancellation. These estimated bits are then sent by the relay node on orthogonal tones in Phase-2 of transmission. The destination nodes receive these bit estimates and use them for interference estimation/cancellation, thus achieving IC benefit in a distributed manner. For this DIC scheme, we analytically derive an exact expression for the bit error rate (BER) in a basic five-node network (two source-destination node pairs and a cooperating relay node) on AWGN channels. Analytical BER results are shown to match with simulation results. For more general system scenarios, including more than two source-destination pairs and fading channels without and with space-time coding, we present simulation results to establish the potential for improved performance in the proposed distributed approach to interference cancellation. We also present a linear version of the proposed DIC.
IEEE Transactions on Wireless Communications, 2012
In this paper, we address the design of codes which achieve modulation diversity in block fading ... more In this paper, we address the design of codes which achieve modulation diversity in block fading singleinput single-output (SISO) channels with signal quantization at receiver and low-complexity decoding. With an unquantized receiver, coding based on algebraic rotations is known to achieve modulation coding diversity. On the other hand, with a quantized receiver, algebraic rotations may not guarantee diversity. Through analysis, we propose specific rotations which result in the codewords having equidistant component-wise projections. We show that the proposed coding scheme achieves maximum modulation diversity with a low-complexity minimum distance decoder and perfect channel knowledge. Relaxing the perfect channel knowledge assumption we propose a novel training/estimation and receiver control technique to estimate the channel. We show that our coding/training/estimation scheme and minimum distance decoding achieve an error probability performance similar to that achieved with perfect channel knowledge.
This book takes a solid step toward a systematic analysis of the implications of microfinance for... more This book takes a solid step toward a systematic analysis of the implications of microfinance for the role and regulation of capital markets. The authors address integration of capital markets with microfinance, technological innovations such as the use of mobile phone technology, the consequences of women’s access to micro-loan borrowings, and the regulatory challenges and opportunities emerging as the landscape of microfinance dramatically evolves.
Infection in the urine tract is more dominate as a medical condition around the world in the hosp... more Infection in the urine tract is more dominate as a medical condition around the world in the hospital and society, especially from young women and pregnant women. The reason for disease the first is uropathogenicEscherichia coli, which has several agents that help in the development that disease in addition to its the capability to stick on a host epithelial cell in urine tract with an assembly the biofilm, which is the most important factor for the disease. Therefore, a vaccine was made for these local isolates to avoid recurrent urinary tract infection and to obtain protective immunity by a laboratory mouse model. After isolation and diagnosis of 90 positive isolates using chrome agardiagnostic from women with urinary tract infection from hospitals in middle Iraq to Wasit province for the period from Jan. 2019 to Apr. 2019. All isolates were tested to detect virulence factors. One isolate was chosen for the determine LD50, immunization and vaccine model, then to estimate the antibody (IgG) level during immunization in the serum of mice at 6 weeks. Results proved that isolates showed positive (71.11%) biofilm, (23.33%) α-heamolysin, (31.11%) serum resistance, and (41.11%) MRHA and (5.55%) MSHA , while LD50=(1*10 10).There are highly significant differences when using isolate in the level of IgG reaches the high peak ranged (749.1 ±20.4) in 6 weeks as compared with control. The results showed that the local vaccine for this isolation provided preventive protection by inducing a protective immune response in mice to protect against infection.
In this paper, we study the achievable rate region of two-user Gaussian broadcast channel (GBC) w... more In this paper, we study the achievable rate region of two-user Gaussian broadcast channel (GBC) when the messages to be transmitted to both the users take values from finite signal sets and the received signal is quantized at both the users. We refer to this channel as quantized broadcast channel (QBC). We first observe that the capacity region defined for a GBC does not carry over as such to QBC. Also, we show that the optimal decoding scheme for GBC (i.e., high SNR user doing successive decoding and low SNR user decoding its message alone) is not optimal for QBC. We then propose an achievable rate region for QBC based on two different schemes. We present achievable rate region results for the case of uniform quantization at the receivers. We find that rotation of one of the user's input alphabet with respect to the other user's alphabet marginally enlarges the achievable rate region of QBC when almost equal powers are allotted to both the users.
In this paper we consider Millimeter wave (mmWave) Massive MIMO systems where a large antenna arr... more In this paper we consider Millimeter wave (mmWave) Massive MIMO systems where a large antenna array at the base station (BS) serves a few scheduled terminals. The high dimensional null space of the channel matrix to the scheduled terminals is utilized to broadcast system information to the non-scheduled terminals on the same time-frequency resource. Our analysis reveals the interesting result that with a sufficiently large antenna array this non-orthogonal broadcast strategy requires significantly less total transmit power when compared to the traditional orthogonal strategy where a fraction of the total resource is reserved for broadcast of system information.
We consider the impact of transceiver power consumption on the energy efficiency (EE) of the Zero... more We consider the impact of transceiver power consumption on the energy efficiency (EE) of the Zero Forcing (ZF) detector in the uplink of massive MIMO systems, where a base station (BS) with M antennas communicates coherently with K single antenna user terminals (UTs). We consider the problem of maximizing the EE with respect to (M, K) for a fixed sum spectral efficiency. Through analysis we study the impact of system parameters on the optimal EE. System parameters consists of the average channel gain to the users and the power consumption parameters (PCPs) (e.g., power consumed by each RF antenna/receiver at BS). When the average user channel gain is high or else the BS/UT design is power inefficient, our analysis reveals that it is optimal to have a few BS antennas and a single user, i.e., non-massive MIMO regime. Similarly, when the channel gain is small or else the BS/UT design is power efficient, it is optimal of have a larger (M, K), i.e., massive MIMO regime. Tight analytical bounds on the optimal EE are proposed for both these regimes. The impact of the system parameters on the optimal EE is studied and several interesting insights are drawn.
We consider Gaussian multiple-input multipleoutput (MIMO) channels with discrete input alphabets.... more We consider Gaussian multiple-input multipleoutput (MIMO) channels with discrete input alphabets. We propose a non-diagonal precoder based on X-Codes in [1] to increase the mutual information. The MIMO channel is transformed into a set of parallel subchannels using Singular Value Decomposition (SVD) and X-codes are then used to pair the subchannels. X-Codes are fully characterized by the pairings and the 2 × 2 real rotation matrices for each pair (parameterized with a single angle). This precoding structure enables to express the total mutual information as a sum of the mutual information of all the pairs. The problem of finding the optimal precoder with the above structure, which maximizes the total mutual information, is equivalent to i) optimizing the rotation angle and the power allocation within each pair and ii) finding the optimal pairing and power allocation among the pairs. It is shown that the mutual information achieved with the proposed pairing scheme is very close to that achieved with the optimal precoder by Cruz et al., and significantly better than mercury/waterfilling strategy by Lozano et al.. Our approach greatly simplifies both the precoder optimization and the detection complexity, making it suitable for practical applications.
We consider a point-to-point mm-wave massive multiple-input multiple-output hybrid beamforming sy... more We consider a point-to-point mm-wave massive multiple-input multiple-output hybrid beamforming system where the transmitter is impaired with in-phase and quadrature-phase imbalance (IQI). We propose a novel channel estimation and IQI parameter estimation algorithm which first estimates the true sparse channel parameters using which it then estimates the IQI parameters. We show that the transmitter IQI limits the spectral efficiency of hybrid beamforming systems at high signal-to-noise ratio irrespective of the choice of hybrid precoder/combiner. We also propose a novel IQI symbol-level pre-compensation scheme at the transmitter which modifies the input symbol vector to the transmit radio frequency (RF) chains in such a way that the symbol vector received at the output of the RF chains is free from any IQI. Analysis and simulations confirm the effectiveness of the proposed IQI pre-compensation technique.
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