Wavelet packet modulation a new equalization scheme

Multicarrier modulation systems have experienced a tremendous growth in complexity and possibilities during the past decade, allowing data transmission rates never before imagined, leading to the commercial appearing of high-definition video on demand on mobile scenarios, faster Ethernet connections, increased number of digital television channels, etc. This tremendous change came up with the application of OFDM in various branches related to information interchange: ADSL and VDSL networks, DVB, WLAN, digital radio, or even the 4th generation standard for mobile communications (LTE). Therefore, OFDM is a cornerstone for communication exchange, but at the same time there are some aspects that might be improved, especially its flexibility and spectral efficiency. Wavelet-Based communication systems have some advantages like lower transmitted signal Sidelobe Level (SLL), higher spectral efficiency as well as higher flexibility with respect to OFDM technology. However, there is an important lack for WPM systems: its structure is complex and there is a lack of specific equalization schemes for it. In this thesis, we will go in deep of the Wavelet Packet System and try to find an equivalent and more efficient model, that leads to a proper specific equalization to improve the characteristics of these systems. Then, after introducing Wavelet theory and the equalization methods, we will present the concept of a post-processing equalization scheme, whose main components will be described in detail. Afterwards the new system will be tested in different scenarios in order to verify and validate theoretical assumptions, to finally conclude this work with a summary of conclussions and related work.Ingeniería de Telecomunicació

Management of borderline ovarian tumours: A comprehensive review of the literature

Borderline ovarian tumours differ from epithelial ovarian cancer by their low incidence, frequent association with infertility, low association with mutations in BCRA genes, different percentages of the most common histological types, early stage diagnosis, and high survival rate, even when associated with peritoneal involvement. They occur in younger women, which is why one of the objectives in these patients will be the preservation of fertility. The management of these tumours has been widely discussed and still continues to be controversial. The latest findings underscore the importance of full staging in both radical and conservative surgery, to choose the most comprehensive treatment and obtain an accurate prognosis. One of the objectives of this article shall be the in-depth review of the indications, benefits, and disadvantages of each type of surgery, as well as the usefulness of the medical treatment. In addition, the article aims to review follow-up guidelines and to clarify the main prognostic factors that affect recurrence and survival of these patients