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This book constitutes the proceedings of the 8th International Conference on Wireless and Satellite Services, WiSATS 2016, held in Cardiff, UK, in September 2016. The conference was formerly known as the International Conference on Personal Satellite Services (PSATS) mainly covering topics in the satellite domain. As the scope of the conference widened to include wireless systems, the conference was renamed WiSATS.
The 22 revised papers were selected from 32 submissions and cover a broad range of related state-of-the-art topics in antennas and mobile terminals, symbol precoding and network coding schemes, energy efficient strategies in satellite communication and cloud radio access networks, smart grid communication and optimization, security issues in vehicular ad-hoc networks (VANET) and delay tolerant net-works (DTN), interference mitigation in high throughput geostationary and non-geostationary satellite systems.

### A Compact CSRR Loaded Monopole Antenna with Defected Ground Structure for Mobile WLAN and WiMAX Applications

Abstract
A physically compact dual band antenna design is presented for use in mobile WLAN and mid-band WiMAX applications. The antenna design is based on a monopole, with a combination of metamaterial inspired features, based on a defected ground structure (GDS) and a complementary split-ring resonator (CSRR). A single CSRR unit cell is placed over a pentagonal monopole antenna, producing a narrow stop-band frequency in the range from 2.40 GHz to 2.49 GHz. The second operating frequency ranges from 3.44 GHz to 6.25 GHz, the broad-banding being due to the influence of the defected ground structure. The antenna design was optimized using HFSS, paying close attention to size constraints, and ease of integration with the radio front end. Simulation results for return loss, gain and radiation pattern are analyzed and presented.
N. A. Jan, A. M. Saleh, M. Lashab, F. M. Abdussalam, L. Djouablia, R. A. Abd-Alhameed

### Development Status of Small-Sized Ka-band Mobile Terminal for Maritime Broadband Communications

Abstract
Most recent development status of small-sized Ka-band mobile communications terminal is presented. The terminal is designed to operate at a minimum target speed of 5 Mbps to/from a Ka-band geostationary satellite, and will eventually be used for the purpose of research activity to explore marine resources within the Exclusive Economic Zone (EEZ) of Japan. The terminal is placed on Autonomous Surface Vehicle (ASV). Because the ASV is “unmanned” and is primarily controlled from a remote ground control station, several mechanisms are embedded into the design for safe and successful operations of the Ka-band terminal. Those key mechanisms are introduced in this paper as they make fault diagnosis easier and increase overall system reliability in case of primary communication channel failure.
Norihiko Katayama, Naoko Yoshimura, Hideo Takamatsu, Susumu Kitazume, Yosuke Takahara, Marshall Lewis, Rowan Gilmore

### New and Less Complex Approach to Estimate Angles of Arrival

Abstract
Accurate angle/direction of arrival (AOA/DOA) estimation is an important issue which, helps mobile communications, wireless positioning and signal processing systems to improve their performance significantly. This paper proposes a new method to estimate the direction of arrival of signals. The proposed estimator is dependent on applying the eigenvalue decomposition (EVD) approach on the covariance matrix of the received signals and then selecting the eigenvector which corresponds to the largest eigenvalue. This method is called Maximum Signal Subspace (MSS). In a novel step, the sidelobes of the pseudo-spectrum are supressed. The theoretical and mathematical model of the proposed method is proved and then verified by computer simulation. The computer simulation is applied to linear antenna array to demonstrate and justify the validity of the new method. The estimation performance and execution time of this method are compared with three AOA methods.
Mohammed A. G. Al-Sadoon, Abdulkareem S. Abdullah, Ramzy S. Ali, Ali S. Al-Abdullah, Raed A. Abd-Alhameed, Steve M. R. Jones, James M. Noras

### MIMO Based Multi Band Antenna for Wireless Communication in C-Band, X-Band, K-Band and Ku Band

Abstract
This paper presents a design of a multiband MIMO microstrip patch antenna. The isolation between the two ports varies from 12.5 dB to 44 dB for all the available bands. Proposed antenna is useful for C-Band, X-Band, K-Band and Ku-Band applications. The proposed antenna shows the circular polarization behavior at 5.27 GHz (5.26 GHz–5.31 GHz), 6.20 GHz (6.18 GHz–6.22 GHz), 11.89 GHz (11.72 GHz–12.24 GHz), 13.56 GHz (13.46 GHz–13.61 GHz), 16.68 GHz (16.55 GHz–16.85 GHz), 21.17 GHz (21.17 GHz–21.20 GHz) and 22.84 GHz (22.28 GHz–22.93 GHz). The proposed antenna is designed on FR-4 substrate with relative permittivity 4.4 and thickness 1.59 mm.
Kunal Srivastava, Ashwani Kumar, Binod Kanaujia, Santanu Dwari, A. K. Verma, Mukul Yadav, Josyula Lalita, S. Chamarthi

### A Staircase-Shaped DGS Structure Monopole Antenna for UWB Operations

Abstract
This paper presents a novel, physically compact, miniaturized, ultra-wideband (UWB) monopole antenna design, which utilizes a defected ground structure (DGS). The defected ground design is realized as a spiral staircase-shaped pattern, and the optimized antenna volume is 26 × 25 × 1.6 mm3. The resultant antenna operates over the full UWB frequency range from 3.1 GHz to 10.6 GHz, with predicted gains in the range 0.1 dBi to 3.36 dBi across the band.
Naeem A. Jan, Mohammed Lashab, Nazar T. Ali, Fathi M. Abdussalam, Embarak M. Ibrahim, Raed A. Abd-Alhameed, M. B. Child

### Implementation of a Low-Rate Linear Step FM Transceiver on a Software Defined Radio Platform

Abstract
Linear FM (Chirp) signals have the merits of constant envelope and insusceptibility to significant carrier frequency offset which particularly suit for low-power low-rate communications. However, the fully digital implementation of the matched filter for the chirp signals is not economically feasible. A low data-rate communication technique using linear step frequency modulated (LSFM) signal was thus proposed which exhibits a complexity reduction in the matched filter implementation with an acceptable performance loss compared to the chirp signals. This paper presents an implementation of such an LSFM transceiver on a realistic commercially available software-defined radio (SDR) platform. Specific system parameters in the LSFM are designed for a furthermore complexity reduction. Implementation cost and experimental results are presented.
Yih-Min Chen, Shin-Chi Liao, Ying-Chang Chen

### High Reliability Light Weight Multi-mission Amplifier System

Abstract
In support of a future ocean broadband projects, a Ka-band mobile satellite communications platform is proposed. To establish a high speed communications link, a high reliability and high power light weight RF amplifier is a key component of the subsystem. The Ka-band High Reliability Light Weight Multi Mission Amplifier system now under development is presented with the technical design and results of ongoing hardware testing. The purpose of this study is to demonstrate that the high reliability of a combined solid state multi-mission power amplifier consisting of many MMIC amplifiers.
Susumu Kitazume, Yosuke Takahara, Chihiro Hayashi, Rowan Gilmore

### Examination of Power Consumption Reduction and Sampling Behavior of Envelope Detection Based Wake-up-Receiver with Duty Cycling Scheme

Abstract
In most communication scenarios where the transmission time is short compared to the idle listening time for a data transmission, most power is consumed by the receiver. This brings up the need for a wake-up-receiver (WuRx) embedded in the system. This work presents a WuRx designed out of commercial components in order to investigate the needs of an WuRx embedded in a WPAN in a real environment setup including WLAN and LTE communication and considering interferer rejection. A system design is presented that fulfills all requirements and is designed with regard to enabling a duty cycle scheme for the reduction of the power consumption. Investigation of the duty cycling behavior is shown, technical difficulties are named and the resulting sampling rate and the power saving capability are analyzed.
Josua Arndt, Lukas Krystofiak, Vahid Bonehi, Ralf Wunderlich, Stefan Heinen

### Bit Synchronization and Delayed Decision Feedback Equalization for EDGE BTS - Hardware Implementation on TMS320C6424 TI DSP

Abstract
This paper demonstrates the implementation of bit synchronization and delayed decision feedback equalization for Enhanced Data rates for GSM Evolution (EDGE) system on TMS320C6424 DSP. EDGE makes use of training sequence for channel estimation and inter symbol interference (ISI) cancellation by use of delayed decision feedback equalization. Modulated baseband in-phase (I) and quadrature (Q) signals are generated using Agilent E4438C Vector signal generator and faded using Agilent fading simulator, is used as input to the DSP. Bit Error Rate (BER) performance of uncoded bits for Packet Data Traffic Channel (PDTCH) meets the EDGE standards. Software implementation uses fixed-point C and Integrated Development Environment (IDE) used for development is code composer studio (CCS). Prototyped our design in Texas Instrument TMS320C6424 DSP and verified for all propagation models as per the EDGE standards. The design and hardware implementation of this Demodulator is done for C-DOT indigenous Shared GSM Radio Access Network (SGRAN) Base Transceiver Station (BTS) project.
Laxmaiah Pulikanti, Pradeep Goutam, Bipsa Purushothaman, K. G. Dileep, S. V. Hari Prasad

### Precoding of Correlated Symbols for STBC Systems Design

Abstract
A problem with transmitting correlated symbols over multiple transmit channel paths is that there is no diversity gain achieved at the receiver. Precoding technique provides a smart approach to achieving diversity gains at the receiver even when correlated symbols are transmitted; by phase variation, amplitude variation or both provided by the precoder. The space-time block code (STBC) technique, for example, is well-known when transmitting the same symbols by making them appear as different symbols using conjugation. We observe that correlated symbols can be transmitted over multiple transmit channel paths over STBC scheme while still achieving diversity. The correlated symbols can be made to appear as different symbols by using precoders; this enables diversity and improves data rate. Combining the proposed with the equivalent channel matrix (EVCM) permits the proposed design to outperform the conventional precoding of uncorrelated symbols technique by 2 dB at all bit error ratio (BER) for $$2 \times 1$$ and $$2 \times 2$$ antenna configurations. This is useful in increasing data rates with better BER performance.
Kelvin Anoh, Bamidele Adebisi, Godfrey Okorafor

### Optimization of Community Based Virtual Power Plant with Embedded Storage and Renewable Generation

Abstract
The current global challenge of climate change has made renewable energy usage very important. There is an ongoing drive for the deployment of renewable energy resource at the domestic level through feed-in tariff, etc. However, the intermittent nature of renewable energy has made storage a key priority. In this work, a community having a solar farm with energy storage embedded in the house of the energy consumers is considered. Consumers within the community are aggregated in to a local virtual power plant. Genetic algorithm was used to develop an optimized energy transaction for the virtual power plant with respect to differential pricing and renewable generation. The results show that it is feasible to have a virtual power plant setup in a local community that involve the use of renewable generation and embedded storage. The results show that both pricing and renewable generation window should be considered as a factor when setting up a virtual power plant that involve the use of storage and renewable generation at the community level. Also, when maximization of battery state of charge is considered as part of an optimization problem in a day ahead market, certain trade-off would have to be made on the profit of the virtual power plant, the incentive of the prosumer, as well as the provision of peak service to the grid.
Oghenovo Okpako, Paul Inuwa Adamu, Haile-Selassie Rajamani, Prashant Pillai

### Assessment of Effective Radiated Power of the Partial Discharge Emulator Source

Abstract
Two effective partial discharge (PD) measurement techniques are used; a galvanic contact measurement technique similar to the IEC 60270 standard measurement and free-space radiometric (FSR) measurement. Several types of PD sources are specially constructed: two internal PD emulators and an emulator of the floating-electrode type. An AC power supply is applied to the PD source and the radiated signal is captured using a wideband biconical antenna. The calibration of PD sources is demonstrated. Effective radiated power (ERP) of the PD sources using a PD calibration device is determined.
Adel Jaber, Pavlos Lazaridis, Bahghtar Saeed, Yong Zhang, Umar Khan, David Upton, Hamd Ahmed, Peter Mather, Robert Atkinson, Martin Judd, Maria Fatima Queiroz Vieira, Ian Glover

### Experimental Privacy Analysis and Characterization for Disconnected VANETs

Abstract
Intelligent Transport Systems (ITS) are special applications of Vehicular Ad-hoc Networks (VANETs) for road safety and efficient traffic management. A major challenge for ITS and VANETs in all its flavours is ensuring the privacy of vehicle drivers and the transmitted location information. One attribute of ITS during its early roll-out stage especially in rural areas and challenged environments is low vehicle density and lack of end-to-end connectivity akin to the attribute of Vehicular Delay Tolerant Networks (VDTNs). This means that contact duration between network entities such as vehicles and road-side units (RSUs) are short-lived. Three popular solutions are the use of pseudonyms, mix-zones, and group communication. Privacy schemes based on the mix-zone technique abound for more conventional VANETs. A critical privacy analysis of such scenarios will be key to the design of privacy techniques for intermittent networks. We are not aware of any work that analyse the privacy problem in intermittent VANTEs. In this paper, we add our voice to efforts to characterize the privacy problem in disconnected VANETs.
Chibueze P. Anyigor Ogah, Haitham Cruickshank, Philip M. Asuquo, Ao Lei, Zhili Sun

### A Mobility-Aware Trust Management Scheme for Emergency Communication Networks Using DTN

Abstract
In the aftermath of a disaster, collecting and disseminating critical information is very challenging. The damage to telecommunication infrastructures makes its extremely difficult to have an effective recovery and relief operation. In this paper, we consider the use of DTN as an alternative measure to temporarily disseminate emergency information in a post disaster scenario using the Post Disaster Model recommended by IETF. We consider internally motivated attacks where responder nodes are compromised thereby dropping packets forwarded to them. We design a Mobility-Aware Trust Management Scheme (MATMS) to mitigate this routing misbehaviour. We evaluate our proposed scheme through extensive simulations and compare our results with existing benchmarks schemes. Our results show that the use of adequate collaborative strategies can improve the performance of DTNs under attack taking into consideration the delivery probability and message delay from source node to the destination node.
Philip Asuquo, Haitham Cruickshank, Chibueze P. Anyigor Ogah, Ao Lei, Kunle Olutomilayo

### Effective Doppler Mitigation in Critical Satellite Communications

Abstract
The modems for telemetry and telecommand applications are a key component in each satellite system: they shall guarantee reliable and effective performance during every mission phases including also critical scenarios such as the control operation of the satellite while it is placed into its orbit, the disposal of a satellite at the end of its life or the deep-space missions. In these scenarios, the link could be unstable and with a rapid variability and the communication become bursty and be characterized by poor performance. This paper introduces an all-digital implementation of a receiver, which is based on the Differential PSK (D-PSK) modulation and an enhanced version of the Digital Delay and Multiplier frequency estimator and compensator for mitigating the Doppler effect, and that results to be perfectly compliant with the aforementioned requirements. The performance of the proposed receiver is extensively studied and compared with an incoherent technique which is based on the Double Differential PSK (DD-PSK) modulation and is known to be suitable for sat-com in critical scenarios.
Alessio Fanfani, Simone Morosi, Luca Simone Ronga, Enrico Del Re

### Interference Mitigation for Multi Spot Beam Satellite Communication Systems Incorporating Spread Spectrum

Abstract
Nonlinear precoding techniques have robust transmit power stability and achieve superior interference suppression when compared to their linear counterparts. Tomlinson-Harashima Precoding (THP) is a suboptimal version of Costa’s well-known work on writing on dirty paper (DPC). Implementing these precoding techniques in a multi spot beam satellite communications system that employs frequency reuse can significantly reduce co-channel interference (CCI). In this paper, we investigate and compare the performance of linear and nonlinear precoding techniques on the forward link of a multiple spot beam satellite link. In addition, we examine the potential benefits of integrating the novel spread spectrum (SS) technique with the existing precoding techniques. The new system’s performance is evaluated and compared with that of standard precoding techniques, and the benefits of incorporating SS are weighed against the extra bandwidth requirements.
Abdulkareem Karasuwa, Jon Eastment, Ifiok Otung

### Specific Rain Attenuation Derived from a Gaussian Mixture Model for Rainfall Drop Size Distribution

Abstract
Precipitation, particularly rain affects the millimetre and sub-millimetre frequencies more severely than it does for lower frequencies in the Earth-space path. There is therefore a need for accurate models that will enable the rainfall drop size distribution (DSD) to be better predicted for better planning and improved service delivery. Using data captured at Chilbolton Observatory, this paper looks at modelling the DSD using the Gaussian Mixture Model (GMM), and attempts to predict the specific attenuation due to rain based on this model and compares the result with other well-established statistical models (lognormal and gamma). Results show that specific attenuation tends to increase with the drop sizes, and the smaller drops contribute little to the overall attenuation experienced by signals. Specific attenuation was computed based on several standard statistical distributions, and compared with that derived from the ITU recommendation.
K’ufre-Mfon E. Ekerete, Francis H. Hunt, Judith L. Jeffery, Ifiok E. Otung

### Cognitive Interference Management Techniques for the Spectral Co-existence of GSO and NGSO Satellites

Abstract
One of the main challenges in the co-existence of geostationary satellite orbit (GSO) and non-geostationary satellite orbit (NGSO) satellite networks is to mitigate the in-line interference caused by an NGSO satellite to the GSO earth terminal, while the NGSO satellite is crossing the GSO satellite’s illumination zone. The method recommended in ITU-R S.1325-3 involves utilizing a range-based power control on the NGSO satellite for downlink communication to the NGSO earth terminals. In this paper, we investigate a cognitive range-based power control algorithm while taking into account the imposed interference level to the GSO fixed satellite service (FSS) system. Results show that the proposed cognitive power control algorithm can mitigate the harmful in-line interference on the GSO terminal receiver, while also providing the desired link quality for the NGSO system. More importantly, we formulate and solve an optimization problem with the objective of minimizing the inter-site distance (ISD) of the GSO-NGSO earth user-terminals. Finally, we develop an analytical method to calculate the ISD between GSO and NGSO earth terminals and validate this with the help of simulation results.
Ameneh Pourmoghadas, Shree Krishna Sharma, Symeon Chatzinotas, Björn Ottersten

### A 15.5 W Si-LDMOS Balanced Power Amplifier with 53% Ultimate PAE for High Speed LTE

Abstract
In this paper, a 15.5 W Si-LDMOS balanced power amplifier (PA) technique operating in the 2.620–2.690 GHz frequency band for LTE systems is presented. The amplifier was designed using large signal Si-LDMOS models, which demonstrated saturation P1dB of 41 dBm and 53% PAE. The AM-AM and AM-PM measured data of the balanced amplifier is extracted and embedded in the device under test (DUT) based on IEEE 802.16 OFDM WLAN Transceiver system. A simple linear model was design for behavioral modelling of memory-less baseband digital pre-distorter. The nonlinearity of the balanced amplifier has been compensated using the Simulink version R2011a.
B. A. Mohammed, N. A. Abduljabbar, M. A. G. Al-Sadoon, K. Hameed, A. S. Hussaini, S. M. R. Jones, F. Elmegri, R. W. Clark, R. Abd-Alhameed

### Energy Efficient Adaptive Network Coding Schemes for Satellite Communications

Abstract
In this paper, we propose novel energy efficient adaptive network coding and modulation schemes for time variant channels. We evaluate such schemes under a realistic channel model for open area environments and Geostationary Earth Orbit (GEO) satellites. Compared to non-adaptive network coding and adaptive rate efficient network-coded schemes for time variant channels, we show that our proposed schemes, through physical layer awareness can be designed to transmit only if a target quality of service (QoS) is achieved. As a result, such schemes can provide remarkable energy savings.
Ala Eddine Gharsellaoui, Samah A. M. Ghanem, Daniele Tarchi, Alessandro Vanelli Coralli

### Distribution of SDTV and HDTV Using VLC Techniques for Domestic Applications

Abstract
This paper presents a visible light communication system that enables flat-panel TVs to receive DVB terrestrial, cable and satellite digital content wirelessly. The benefits of VLC over Wi-Fi and power-line networking based solutions are discussed, and the physical requirements of the system are defined. The paper also discusses how the MPEG transport stream of a set-top-box can be re-encoded for transmission over a free-space optical channel using a novel PPM modulation scheme.
Timothy J. Amsdon, Martin J. N. Sibley, Peter J. Mather

### On the Energy Minimization of Heterogeneous Cloud Radio Access Networks

Abstract
Next-generation 5G networks is the future of information networks and it will experience a tremendous growth in traffic. To meet such traffic demands, there is a necessity to increase the network capacity, which requires the deployment of ultra dense heterogeneous base stations (BSs). Nevertheless, BSs are very expensive and consume a significant amount of energy. Meanwhile, cloud radio access networks (C-RAN) has been proposed as an energy-efficient architecture that leverages the cloud computing technology where baseband processing is performed in the cloud. In addition, the BS sleeping is considered as a promising solution to conserving the network energy. This paper integrates the cloud technology and the BS sleeping approach. It also proposes an energy-efficient scheme for reducing energy consumption by switching off remote radio heads (RRHs) and idle BBUs using a greedy and first fit decreasing (FFD) bin packing algorithms, respectively. The number of RRHs and BBUs are minimized by matching the right amount of baseband computing load with traffic load. Simulation results demonstrate that the proposed scheme achieves an enhanced energy performance compared to the existing distributed long term evolution advanced (LTE-A) system.
Tshiamo Sigwele, Atm Shafiul Alam, Prashant Pillai, Yim Fun Hu