Mobility of sensor nodes in wireless sensor network (WSN) has posed new challenges particularly in packet delivery ratio and energy consumption. Some real applications impose combined environments of fixed and mobile sensor nodes in the same network, while others demand a complete mobile sensors environment. Packet loss that occurs due to mobility of the sensor nodes is one of the main challenges which comes in parallel with energy consumption. In this paper, we use cross layer design between medium access control (MAC) and network layers to overcome these challenges. Thus, a cluster based routing protocol for mobile sensor nodes (CBR-Mobile) is proposed. The CBR-Mobile is mobility and traffic adaptive protocol. The timeslots assigned to the mobile sensor nodes that had moved out of the cluster or have not data to send will be reassigned to incoming sensor nodes within the cluster region. The protocol introduces two simple databases to achieve the mobility and traffic adaptively. The proposed protocol sends data to cluster heads in an efficient manner based on received signal strength. In CBR-Mobile protocol, cluster based routing collaborates with hybrid MAC protocol to support mobility of sensor nodes. Schedule timeslots are used to send the data message while the contention timeslots are used to send join registration messages. The performance of proposed CBR-Mobile protocol is evaluated using MATLAB and was observed that the proposed protocol improves the packet delivery ratio, energy consumption, delay and fairness in mobility environment compared to LEACH-Mobile and AODV protocols.

Mobility of sensor nodes in wireless sensor network (WSN) has posed new challenges particularly in packet delivery ratio and energy consumption. Some real applications impose combined environments of fixed and mobile sensor nodes in the same network, while others demand a complete mobile sensors environment. Packet loss that occurs due to mobility of the sensor nodes is one of the main challenges which comes in parallel with energy consumption. In this paper, we use cross layer design between medium access control (MAC) and network layers to overcome these challenges. Thus, a cluster based routing protocol for mobile sensor nodes (CBR-Mobile) is proposed. The CBR-Mobile is mobility and traffic adaptive protocol. The timeslots assigned to the mobile sensor nodes that had moved out of the cluster or have not data to send will be reassigned to incoming sensor nodes within the cluster region. The protocol introduces two simple databases to achieve the mobility and traffic adaptively. The proposed protocol sends data to cluster heads in an efficient manner based on received signal strength. In CBR-Mobile protocol, cluster based routing collaborates with hybrid MAC protocol to support mobility of sensor nodes. Schedule timeslots are used to send the data message while the contention timeslots are used to send join registration messages. The performance of proposed CBR-Mobile protocol is evaluated using MATLAB and was observed that the proposed protocol improves the packet delivery ratio, energy consumption, delay and fairness in mobility environment compared to LEACH-Mobile and AODV protocols.

Low-power wireless personal area network (LoWPAN) consists of large number of resource constraint devices connected over a wireless link with the aim of gathering real time information and transmitting it to desired application and vice versa. This requires transmission of IPv6 packets over Low-power wireless personal area network and is called 6LoWPAN. The large sized headers like IPv6, TCP, and UDP consume most of the packet space leaving only 28 bytes for actual payload. MTU of 802.15.4(IEEE standard for wireless network) is only 127 bytes much less as compare to IPv6 packet which is of 1280 bytes. Hence Header compression and fragmentation becomes a necessity in 6LoWPAN so as to provide reasonable number of bits for payload. This paper depicts 6LoWPAN protocol stack and various header compression techniques for compressing IPv6 header. It also shows comparison among various techniques on the basis of total number of bits needed in compressed IPv6 header under various scenarios.

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A low-profile Multiple Input Multiple Output (MIMO) antenna showing dual polarization, low mutual coupling, and acceptable diversity gain is presented by this paper. The antenna introduces the requirements of fifth generation (5G) and the satellite communications. A horizontally (4.8–31 GHz) and vertically polarized (7.6–37 GHz) modified antipodal Vivaldi antennas are simulated, fabricated, and integrated, and then their characteristics are examined. An ultra-wideband (UWB) at working bandwidths of 3.7–3.85 GHz and 5–40 GHz are achieved. Low mutual coupling of less than −22 dB is achieved after loading the antenna with cross-curves, staircase meander line, and integration of the metamaterial elements. The antennas are designed on a denim textile substrate with = 1.4 and h= 0.5 mm. A conductive textile called ShieldIt is utilized as conductor with conductivity of 1.8 × 104. After optimizing the proposed UWB-MIMO antenna’s characteristics, it is increased to four elements positioned at the four corners of a denim textile substrate to be employed as a UWB-MIMO antenna for handset communications, 5G, Ka and Ku band, and satellite communications (X-band). The proposed eight port UWB-MIMO antenna has a maximum gain of 10.7 dBi, 98% radiation efficiency, less than 0.01 ECC, and acceptable diversity gain. Afterwards, the eight-ports antenna performance is examined on a simulated real voxel hand and chest. Then, it is evaluated and compared on physical hand and chest of body. Evidently, the simulated and measured results show good agreement between them. The proposed UWB-MIMO antenna offers a compact and flexible design, which is suitably wearable for 5G and satellite communications applications.

Abstract. In 6LoWPAN, IPv6 is capable to provide identity and wireless embedded internet aims for efficiently providing IP global connectivity for wireless, small size, low power, low rate, limited memory and limited computation capabilities embedded smart objects. However, the relatively huge header size of upper layer protocols (e.g. TCP, UDP and IPv6) will deplete the frame payload to approximately 33 bytes. Some schemes had been designed to compress the headers to provide more space for the data payload. Recently, a standalone operation mode for Second and Subsequent Fragments Headers Compression (S&SFHC) scheme for header compression in 6LoWPAN has been proposed. This scheme exploits the correlation between the first and the subsequent fragments' headers to avoid carrying the redundant headers of second and subsequent fragments. In this paper, an extended version of S&SFHC for 6LoWPAN is proposed. This new scheme is introduced by integrating S&SFHC with other existing scheme like LOWPAN_IPHC. When the proposed new scheme incorporates with another scheme, the existed scheme is used to compress the header for the first fragment only. The second and subsequent fragments will be compressed by using S&SFHC scheme. The integration between S&SFHC and LOWPAN_IPHC schemes can achieve up to 30% and 10% higher packet delivery ratio, 30% and 10% higher throughput, 18% and 6% lower average delay, 24% and 4% lower average energy consumption compared to LOWPAN_IPHC and S&SFHC standalone mode respectively when the packet size is 600 bytes.

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Coverage degree and mobility have acquired a lot of attention lately in Wireless Sensor Network (WSN). This paper shows that nodes mobility can enhance coverage degree for WSN. Analytical model is introduced to describe the coverage degree in mobile nodes wireless sensor network. MATLAB was used to build the simulator. The analytical work is validated by simulated results. Both of analytical model and simulation showing that the coverage degree has been enhanced in Mobile Nodes Wireless Sensor Network (MNWSN) as compared to static network.