Power Constrained Space-Time Processing for Suppression of Electromagnetic Fields

Active suppression of noise and vibrations is a well established field of research with many applications in acoustic and mechanical industries. In this paper we investigate the possibility of applying these adaptive active control methods with the aim of lowering the electromagnetic power density at a specific volume in space using the superposition principle and space-time processing employing the full MIMO (Multiple Input Multiple Output) antenna system setup. The application that we evaluated is a model of a mobile phone equipped with one ordinary transmitting antenna and two actuator-antennas whichpurpose is to cancel out the electromagnetic field at the human head while maintaining a predefined level of the overall output power of the system. This power control is achieved through the use of a quadratic constraint on the active control algorithm. Simulation results show the promise of using the adaptive control algorithms and MIMO system to attenuate the electromagnetic field power density.

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Application of Space-Time Signal Processing and Active Control Algorithms for the Suppression of Electromagnetic Fields

Applied Signal and Image Processing ◽

10.4018/978-1-60960-477-6.ch003 ◽

2011 ◽

pp. 45-60

Author(s):

Tommy Hult ◽

Abbas Mohammed

Keyword(s):

Active Control ◽

Mobile Phones ◽

Processing System ◽

Antenna System ◽

Space Time ◽

Control Algorithms ◽

Time Signal ◽

Suggested Approach ◽

Mimo Antenna ◽

Effects Of Radiation

Several studies have been conducted on the effects of radiation on the human body. This has been especially important in the case of radiation from hand held mobile phones. The amount of radiation emitted from most mobile phones is very small, but given the close proximity of the phone to the head it might be possible for the radiation to cause harm. The suggested approach involves the use of adaptive active control algorithms and a full space-time processing system setup (i.e. multiple antennas at both the transmitter and receiver side or MIMO), with the objective of reducing the possibly harmful electromagnetic radiation emitted by hand held mobile phones. Simulation results show the possibility of using the adaptive control algorithms and MIMO antenna system to attenuate the electromagnetic field power density.

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A Novel Joint Transmitting and Receiving Antenna Selection for Spatial Multiplexing Systems

Applied Mathematics and Nonlinear Sciences ◽

10.2478/amns.2020.2.00031 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Mingjie Zhuang ◽

Haitao Li ◽

Yisong Lin

Keyword(s):

Computational Complexity ◽

Optimal Algorithm ◽

Antenna Selection ◽

Mimo System ◽

Antenna System ◽

Spatial Multiplexing ◽

Mimo Channel ◽

Maximum Capacity ◽

Receiving Antenna ◽

Transmitting Antenna

AbstractHow to reduce the hardware cost and high power consumption of RF link of communication device is the key problem to be solved for multi-transmitting antenna and multi-receiving antenna system (MIMO). Always choose the best antennas connection a limited number of RF circuits, which is called antenna selection technology (AS), are a perfect solution to the problem, Assuming that the spatial range of the antenna meets the requirements of signal multiplexing and based on the maximum capacity criterion of the selected MIMO system, the manuscript proposes a low computational complexity (CC) and high performance joint transmitting and receiving antenna selection technique (JTRAS). Starting from the traditional capacity formula and the full matrix of MIMO channel, we utilize a simplified channel capacity expression through repeatedly iterating to delete a row and a column of the equivalent decrement channel matrix, which is to remove a pair of transmitting and receiving antennas. Based on the decreasing JTRAS (DJTRAS) algorithm, the capacity results of simulating calculation indicate that its median capacity overtakes other ones, such as optimum selection (OS), AS based on Frobenius 2 norm (NBS), and concise joint AS criterion (CJAS) etc., and the novel DJTRAS scheme can significantly reduce computational complexity (CC) compared to the exhaustive search method with maximum capacity, which defined as optimal algorithm in the curve graphs. This new technology of the AS is particularly suited to large number of selected antennas, such as Lt ≥ NT/2,Lr ≥ NR/2.

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Analysis between Various Random MIMO Systems Model on the Basis of Channel Capacity

10.20944/preprints201607.0078.v2 ◽

2016 ◽

Author(s):

Shree Krishna Acharya

Keyword(s):

Outage Probability ◽

Channel Capacity ◽

Mimo Systems ◽

Mimo System ◽

Antenna System ◽

System Model ◽

Mimo Channel ◽

Systems Model ◽

Capacity Model ◽

Transmitting Antenna

Finding a good MIMO system model also major issue in Wireless Communication system. It is facing with so many problem, one of the major problem is finding good system model in terms of capacity and transmitting antenna system. In this paper, we analyze the channel capacity of various MIMO system model with some constant SNR level and outage probability. We establish a novel idea for MIMO system models as consider as 2N- MIMO system model and find-out change in channel capacity when different transmitting antennas with constant SNR and outage probability. The channel capacity ratio CCR is presented here on the basis of 2N- MIMO channel capacity model. Number of transmitted antenna presented in MIMO system is increases is well-known however paper shows change in capacity in simple form.

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