In this paper, we develop a novel approach for a joint platform of radar and communication systems. The previous approaches for dual-function radar-communication systems focused only on the simultaneous transmission of radar and communications in radar active mode. To increase the throughput of communications without affecting the radar operation, we enable communication during the whole pulse repetition interval by using two generalized sidelobe cancellers. We propose two different operational modes of the dual-function radar-communications system. In active mode, the radar function is achieved through the mainlobe, and communications are achieved through the sidelobes. In active mode, only one generalized sidelobe canceller is functional. In rest mode, both the generalized sidelobe cancellers are functional. The first generalized sidelobe canceller has the mainlobe and sidelobe levels as in active mode, and the second generalized sidelobe canceller has the same mainlobe level but double the power in the sidelobes. The output is the difference between the two, in which the mainlobe is canceled, while the sidelobes have the same power, as in the case of active mode. The effectiveness of the proposed scheme is investigated in terms of the bit error rate. Moreover, the proposed system allows communication during the whole pulse repetition interval, thus, enhancing the throughput tremendously.INDEX TERMS Radio spectrum management, radar signal processing, array signal processing, transmitters, wireless communication, radar antennas, multiuser detection, linear antenna arrays and multiaccess communication.

A uniform linear array ofnantenna elements can steer up ton-1nulls. In situations where less thann-1nulls are required to be steered, the existing algorithms have no criterion to utilize the remaining weights for sidelobe suppression. This work combines sidelobe suppression capability with null steering by independent weight control. For this purpose, the array factor is transformed as the product of two polynomials. One of the polynomials is used for null steering by independent weight control, while the second one is for sidelobe suppression whose coefficients or weights are determined by using convex optimization. Finally, a new structure is proposed to incorporate the product of two polynomials such that sidelobe suppression weights are decoupled from those of null steering weights. Simulation results validate the effectiveness of the proposed scheme.

In the literature a technique for sidelobe suppression is presented that utilizes product of two polynomials. In this paper, a method is presented for efficient sidelobe suppression by proper selection of sidelobe region. For this purpose, it is proposed to observe the radiation pattern of the first polynomial to find out the position of right and left nulls adjacent to the main beam. The region outside these nulls is proposed to be utilized for sidelobe region while finding the weights of second polynomial that is meant for sidelobe suppression. This will provide maximum overlap of main beams of the two polynomials and suppress sidelobes efficiently. Simulation results confirm the validity of the proposed method.

Introduction. Parental involvement in children’s education means engagement and participation of parents in the educational activities of their children. The existing body of empirical research shows that parental involvement can influence academic performance of their children in two distinct ways, i.e. parental involvement in children education at home (helping children in homework and other academic discussions, etc.) and parental involvement in children education at school (participation in school function and meetings, etc.). Active involvement of parents in children’s education may even counterbalance the unfavourable effects of low socioeconomic status and underprivileged neighborhood. The overall effect of parental involvement in child education both at home and at school is a worthy source of improving the academic performance of children through securing higher grades at school.Aim. This research aimed to examine the effects of parental involvement in children education at home on academic performance of secondary schools students and to identify the difference of the effects of parental involvement on students of different gender, parent literacy status and parent importance to children education.Methodology and research methods. Cross sectional and a multistage stratified sampling technique was adopted to portray information from sample of 448 students on Likert scale. Chi square, Kendall’s Tau-c tests and Logistic regression analyses were used to determine the level, direction and strength of association among variables.Results. The results showed that the association of children academic performance was significant and positive when parents helped children with their homework (P = 0.000, Tc = 0.231), discussed school progress with children (P = 0.002, Tc = 0.122) and motivated children to work harder when they make a poor grade (P = 0.015, Tc = 0.133). Moreover, the results highlighted variation in the academic performance of children with respect to their gender, parental literacy status, parental importance to children education and parental involvement in children education at home. It was concluded that boys, children of literate parents, children whose parents give more importance to their education and their parents remain involved in their educational activities at home secured higher grades.Scientific novelty. The present study is distinctive in that it examined variations in children’s academic performance with respect to student gender, parental literacy status, and parental importance to their education in addition to focusing on the relationship between parental involvement in their children education at home and academic performance.Practical significance. The analysis of the research outcomes leads to several interesting results and proposes helpful suggestions for important stakeholders. The main study recommendations that will enable parents to promptly meet the educational demands of their children in order to aid them in getting better grades include awareness-raising campaigns for parents, income creation chances for disadvantaged families, and adult literacy initiatives.