RF Transceiver system design for IoT in wide area networks

Abstract. Wireless communication has grown rapidly in the last two decades. New applications and advancement in technology is boosting the demand. Internet of things (IoT) is nowadays topic of discussion for everyone related to the wireless communication industry. IoT is a system of interconnected devices which can be people, animals, things or machines each with a unique identifier and the ability to transfer data over a network without any interaction with humans or computers. The aim of this thesis is system design of RF transceiver for IoT devices operating in wide area networks. Several service providers are struggling to capture the IoT market. In this thesis detailed system design of third generation partnership project (3GPP) newly specified user equipment category M1 also known as long term evolution machine (LTE-M) is presented. LTE-M can operate in both full duplex and half duplex and it uses the same signal structure as the current operational standard long term evolution (LTE). The designed transceiver is able to operate in half duplex and meet the performance requirement (95 % throughput) specified by 3GPP. Radio frequency transceivers have various architectures and each architecture has its own pros and cons associated with it. This transceiver is designed to be integrated in a wearable device. Constraints like small size and low power restrictions led to the choice of direct conversion architecture for the design. Simulations were performed in ADS to verify the theoretical results

Multi-user MIMO beamforming:implementation, verification in L1 capacity, and performance testing

Abstract. A certain piece of technology takes a lot of effort, research, and testing to reach the productisation phase. Radio features are implemented in layer 1 (L1) before moving to the hardware implementation phase, where their functioning is tested and verified. The target of the thesis is to implement and verify beamforming based multi-user multiple-input multiple-output (MU-MIMO) in L1 capacity and performance testing (PET) environment. The L1 testing environment mainly focuses on 4G and 5G stand-alone (SA) cases, while the focus of this thesis work is only on 5G SA technology, which features beamforming and MU-MIMO. Beamforming and MU-MIMO have been tested in an end-to-end system but not specifically in L1. The L1 testing provides a deeper analysis of beamforming and MU-MIMO in L1 and aids in problem identification at an early productisation phase, saving both time and money. L1 PET has multiple components that work together for L1 data transmission in both uplink (UL) and downlink (DL) directions and handle the verification of the transmitted data. The main components that play a key role in the implementation of multi-user MIMO beamforming concern frame design setup, message setup for UL and DL using correct channels and interfaces, transmission of the generated data in UL and DL, and message capturing at L1 end (whether correct messages are transmitted or not). For verification purposes, methods such as analysing plots from L1 log results based on comparison with radio specifications are used to determine whether the generated test output is correct or not. Finally, performance metrics, such as error vector magnitude (EVM), UE per transmission time interval (TTI), number of layers per UE, channel quality indicator (CQI), physical resource block (PRB) count, and throughput, are evaluated to assess the capacity and performance correctness of the implemented test setup

Giant ganglioneuroma in a 5-year child

ABSTRACT We report a 5-year boy presenting with pain in the lower chest and upper abdomen. On evaluation with computed tomography scan of the chest, he was found to have a large 16 x 14 cm posterior mediastinal mass compressing the inferior vena cava and liver, and shifting the heart to the opposite side. Tumor was approached via right postero-lateral thoracotomy and dissected off from esophagus, heart, inferior vena cava and lungs. The entire tumor was resected without any complications. Postoperative course was unremarkable. Resection of the tumor was successful. The histopathology showed it to be giant ganglioneuroma with no evidence of malignancy

Myxoid liposarcoma originating in the anterior mediastinum

Myxoidliposarcomas ofthe head and neck aremostly metastaticin nature, with the primarylesion usually in lower extremities or retroperitoneum. Primary mediastinal liposarcomas are even rare Although there have been previous cases reporting their incidence, there is no evidence of any case comprising of both the neck and the mediastinal region yet. We here present a case of a 43 year old male with a primary liposarcoma of the myxoid subtype originating in the anterior mediastinumThis is the first time such a case haspres ented in literature. The patient presented with a right sided neck swelling associated with pain and shortness of breath upon lying down.CT neck revealed an enhancing mass extending from right cervical regionto axilla and enca sing the subclavian artery and involving a portion of the right lung. The patient underwent wide local excision of the mass along with chemo radiotherapy to prevent recurrenc

Hernia of morgagni presenting as constipation in a 65-year-old male

Hernia of Morgagni is congenital defects in the diaphragm. They are mostly asymptomatic and present with vague symptoms when they do so. A high index of suspicion is required for timely diagnose of this condition. Here we present the case of a 65-year-old male patient presented to our institute with constipation for the past six months. Chest radiology raised the suspicion of a hernia which was further confirmed by contrast studies. Laparotomy was done and the hernia sac identified, colon and greater omentum reduced and defect repaired. He was discharged in stable condition and was doing well on follow-up

Successful management of a stab wound to the left ventricle

A 24 year old male presented to the emergency room with a 2 hour history of knife stab wound. He was haemodynamically stable with good bilateral air entry. However on X-ray an enlarged cardiac silhouette was seen. The patient suddenly became hypotensive and on suspicion of cardiac tamponade a catheter was introduced in pericardial space, but the measure was unsuccessful and he was rushed to the Operating Room. During the surgery a 2 cm long laceration was identified in the mid-left ventricular (LV) wall less than 1mm away from the Left Anterior Descending (LAD) Artery. The Left Anterior Descending Vein was damaged which was then repaired along with the ventricular wall by the interrupted pledgeted 3-0 prolene suture, whilst a cardiopulmonary bypass was kept on the stand by. The patient was checked for a ventricular septal defect via an intraoperative echocardiography. Subsequently, he had an uneventful recovery and was discharged

Management of penetrating injury to thoracic inlet and lower neck with retained foreign body using video assisted thoracoscopic surgery

Penetrating neck and chest injuries are a common form of occupational injuries. We hereby report a unique case in which a metallic rod had penetrated the left chest and neck of a plastic factory worker. The patient was vitally stable when he presented to Emergency Room. Chest X-ray was performed and the patient was rushed to the operating room. VATS (video assisted thoracoscopic surgery) and neck dissection was done for retrieval of the metallic rod. On table, endoscopy was also done to rule out injury to oesophagus. No injury to vital structures was found and the subsequent recovery was uneventful

Successful resection of lymphangioma of the neck and mediastinum presenting as stridor in a 12 year old child

Lymphangiomas are congenital malformations of lymphatic tissue. This benign condition is generally found in the neck region and is discovered by 2 years of age. Here we report the case of a 12 year old child who presented with a cervical and mediastinal cystic hygroma that had progressed to such a space occupying nature as to cause the shifting of the trachea. The entire mass was successfully resected with a lower neck incision. Our case suggests the necessity of considering cystic lymphangioma in the differential diagnosis of lateral neck masses and use of adequate imaging to substantiate the preoperative diagnosis

Retrograde bullet migration from inferior vena cava into right common iliac vein following gunshot: a case report

Abstract Bullet embolization cases are rare and even rarer are its retrograde migration in the veins. We report the case of a 14 year old male with a gunshot wound to the left side of his chest. CT scan revealed bilateral haemothorax and foreign body in the right common iliac vein. The patient was immediately taken to the operating theatre and median sternotomy performed. Bullet entry tear was found in the inferior vena cava however, the bullet was found lodged in the right common iliac vein and slipped down against the flow of blood. The bullet was left in situ and after the necessary repair the chest was closed and the patient shifted to the CICU and discharged after 4 days in stable condition. Patient was followed after 1 week and reassured and advised for one year follow-up