Broadband microwave diode mixer design and implementation

2016
Koç, Emrah
Mixers play a critical role in design and development of wireless communication systems. Demanding requirements of the mixers are improvements in conversion efficiency, bandwidth, cost, and linearity. Schottky barrier diodes attract mixer designers due to their favorable characteristics leading to wide bandwidth, low-cost, and high efficient designs. This thesis demonstrates the design and implementation of two passive mixing circuits using Schottky barrier diodes at microwave frequencies. The first circuit is a broadband mixer which operates between 2 GHz and 18 GHz for RF/LO frequency with an average conversion loss of 7 dB. It provides LO-RF and RF-IF isolation of 30 dB over the most frequencies across the band. Furthermore, IIP3 of 13 dBm is achieved for LO drive level of 13 dBm. The second design proposes improved IF bandwidth up to 4 GHz. Conversion loss of 6 dB is typically measured for the RF frequency of 5 GHz-15 GHz. It shows excellent LO-RF isolation of better than 35 dB across the frequency band with similar IIP3 performance of first design.  

Suggestions

X-band high power GaN power amplifier design and implementation
Işık, Ali İlker; Demir, Şimşek; Department of Electrical and Electronics Engineering (2016)
High frequency power amplifiers play a crucial role in design, development and overall performance of wireless communication systems. Demanding requirements of the power amplifiers require improvements in output power, efficiency and bandwidth. GaN devices attract high frequency power amplifier designers due to the superior material characteristics of GaN. In this thesis, a power amplifier operating at X-band is designed and realized using a GaN discrete bare die transistor. It provides over 15 W output pow...
Cooperative relaying schemes for narrow-band frequency hopping wireless ad hoc networks
Yenihayat, Güven; Onat, Furuzan Atay; Kolaǧasioǧlu, Ertuǧrul; Yılmaz, Ali Özgür (2011-08-29)
Cooperative relaying is a promising technique for improving the performance of weak communication links in wireless networks by exploiting spatial diversity induced by relay transmissions. This paper considers cooperative relaying schemes for a narrow- band frequency hopping system. A novel hybrid relaying scheme called opportunistic hybrid relaying, which is specifically designed for this system, is presented. Unlike most relaying schemes in the literature, opportunistic hybrid relaying uses bandwidth effi...
Energy-Aware Data Delivery Framework for Safety-Oriented Mobile IoT
Al-Turjman, Fadi (2018-01-01)
The proliferation of wireless multimedia sensor networks has given rise to intelligent transportation systems as a mobile data-sharing model. This vision can be extended under the umbrella of the mobile Internet of Things to include versatile resources, such as smartphones, radio frequency identification tags, and sensors on roads that can be utilized in emergency situations. The facilitation of such a vision faces key challenges in terms of interoperability, resource management and energy consumption. In t...
Blind channel estimation based on the Lloyd-Max algorithm innarrowband fading channels and jamming
Dizdar, Onur; Yılmaz, Ali Özgür; Department of Electrical and Electronics Engineering (2011)
In wireless communications, knowledge of the channel coefficients is required for coherent demodulation. In this thesis, a blind channel estimation method based on the Lloyd-Max algorithm is proposed for single-tap fading channels. The algorithm estimates the constellation points for the received signal using an iterative least squares approach. The algorithm is investigated for fast-frequency hopping systems with small block lengths and operating under partial-band and partial-time jamming for both detecti...
Design of a reduced complexity rateless spinal decoder
Taş, Murat; Diker Yücel, Melek; Department of Electrical and Electronics Engineering (2014)
Wireless communication systems utilize several forward error correcting techniques to cope with changing channel conditions efficiently. One way is selecting from a list of coding/modulation schemes by considering the actual channel state. When this approach of choosing a fixed rate code is not applicable, one can use rateless codes whose rates are dynamically changing with respect to the changing channel conditions. A rateless encoder continues to send its codeword/packet to the destination unless the rece...
Citation Formats
E. Koç, “Broadband microwave diode mixer design and implementation,” M.S. - Master of Science, Middle East Technical University, 2016.