Fourth Year Projects for 2013-2014

Group Project in Radio Frequency and Analog Design

Radio On A Chip

As in previous years, it is expected that this will be joint between students reporting to Prof. Plett and Prof. Rogers.

As in previous years we expect to be working on a radio circuit. Similar to 2012-2013 but Unlike years before that, we hope to be able to do the full integration at Carleton University so that our target will be to have a working prototype by the end of the project. The process available to us at Carleton university would likely not allow us to do designs at multiple GHz, but it should be possible to build a radio operating at some hundreds of MHz, for example in the FM radio band.

We expect the project will be similar to the previous year, in which an FM radio was built (more detail below). Since that was the first year to do a project in this process, there were many lessons learned which can be applied this year. For example, it is important right from the start to think about how a circuit will be tested. With that in mind, one of the early steps this year would be to test some of the circuits from the previous year before going on to the design phase. Reading more below about projects from last year and previous year will give you some idea of what to expect for this year.

In the past year, (2012-2013), students worked on an FM radio operating from 88 to 108 MHz, making use of the Carleton process, also being used for ELEC 4609 projects. However, while 4609 made use of 5 micron transistors, our group was the first group to do circuit design using 2.5 micron transistors, allowing designs up to a few hundred MHz. There were 8 students in the group with the following parts worked on: building the follwoin various parts of the radio including an LNA, feedback-based channel select filter, mixer, PLL-based FM demodulator, voltage-controlled oscillator, frequency synthesiszer and power amplifier. In addition, there was one person working on providing transistor modeling and providing support in the fabrication facility. Expect that more detail will be added here later.

  1. A Low Noise Amplifier (LNA), operating at RF frequencies 88-108 MHz
  2. feedback-based quadrature channel select filter,
  3. mixer used in downconverting RF at 88-108 to IF at 10.7 MHz,
  4. PLL-based FM demodulator operating at 10.7 MHz,
  5. voltage-controlled oscillator generating quadrature signals (sine and cosine) in the 100 MHz range.
  6. frequency synthesiszer parts such as dividers and phsae detector,
  7. power amplifier with ouput in the 88-108 MHz range.
  8. transistor modeling to support all the simulations and support in the fabrication facility.
Steps involved background research, simulation and layout and all parts were fabricated. Not all parts were tested, particularly where RF frequencies were required or where a large number of simultaneous connections were needed. Such parts could wire bonding on to printed circuit boards and such boards were not completed on time. In future years, testing should be considered early enough to allow design for test, e.g., use RF probe pads for 100 MHz signals, and design printed circuit boards where needed in parallel with the actual integrated circuit work.

Expect more details later.

In the previous year, (2011-2012), students worked on a 2.6 GHz radio - this is a frequency used for a particular variation of LTE or 4G radio so students were able to say they were working on components relevant to the next generation of cell phone.

Students started by exploring the architecture and the required tools with help from the professors and some of their graduate students. Then from a list of possible components, students chose particular components to work on as the main focus of their work. For 2011-2012, there were three students that worked on the following three parts:

  1. a low noise amplifier (LNA) that picks up the small signal from the antenna and amplifies it without adding too much noise, then passes it on to the mixer.
  2. a passive downconverting mixer that takes the RF signal from the LNA and mixes it with a local oscillator signal, with the output at baseband.
  3. A power amplifier that amplifies the RF signal to sufficient power to be transmitted by the antenna.
After selecting the parts, these components were further explored and implemented as an integrated circuit in a commercial 130 nm process using industry standard tools. Steps included schematic level design and simulation, layout, and extraction of parasitics from the layout to obtain a more accurate simulation. Monte Carlo simulations were run to determine the effect of process variations and mismatch between components. Finally the intention was for all students to combine their blocks to form a complete transceiver.

By comparson, in 2010-2011, six students built components for an ultrawideband transceiver. The particular components developed by the students were:

  1. a 3-5 GHz LNA,
  2. a broadband mixer,
  3. a 1 Gs/s A/D converter,
  4. a PA operating from 3 to 5 GHz,
  5. a PA operating from 6-10.6 GHz,
  6. a 16 GHz oscillator.

Examples of other components that could have been chosen would have been the integrated baseband filters, a D/A converter, and frequency synthesizer components.

In earlier years, other topics have included 60 GHz radio, wireless LAN, and Bluetooth radio.

Description from an earlier year.

While cellular and WLAN applications are some of the best known applications for radio frequency integrated circuits (RFICs), another very active area that has generated much interest is the design ultra wide band (UWB) systems for personal area networks (PAN) and other low power applications. Unlike narrow band wireless applications, UWB systems must handle many signals simultaneously over a wide frequency range.

Students in the project will be responsible for the design of a high frequency (either in the 3-10GHz range or in the 60GHz range) circuit building block and may also be expected to participate in designing the radio architecture. The circuit blocks will be designed in either a 130nm or 65nm state of the art CMOS process, using the same tools used in industry.

This project will make use of the skills students have developed in ELEC 2507, and ELEC 3509. Enrollment in courses such as ELEC 4505, and ELEC 4707 will provide additional background for the project. This project will be run jointly with Professor Rogers.