Skip to main content

Jacques Christophe Rudell

  • Associate Professor

Jacques Rudell joined the Electrical Engineering Department as an assistant professor in January 2009. He has a BS in electrical engineering from the University of Michiganand MS and Ph.D. degrees in electrical engineering from the University of California, Berkeley. From 1989 to 1991, Rudell was an IC Designer and Project Manager with Delco Electronics (now Delphi), where he focused on bipolar analog circuits for automotive applications. From 2000 to 2001, he was a postdoctoral Researcher at the University of California, Berkeley, in addition to holding consulting positions in several Silicon Valley firms. In early 2002, he joined Berkana Wireless (now Qualcomm), San Jose, Calif., as an Analog/RF IC Design Engineer and later became the Design Manager of the Advanced IC Development Group. From 2005 to 2008, he worked in the Advanced Radio Technology Group at Intel, where his work focused mainly on RF transceiver circuits and systems, in advanced silicon processes.

Rudell received the National Science Foundation CAREER award for his work related to mmWave CMOS IC design. He has served on the IEEE International Solid-State Circuits Conference technical program committee (2003-2010), and on the RFIC steering committee (2002-2013) where he was the 2013 General Chair. He was also an Associate Editor for the IEEE Journal of Solid-State Circuits (2009-2015). Rudell is currently a member of the IEEE European Solid-State Circuit Conference’s technical program committee.

Research Interests

RF, mm-Wave, Analog and Mixed-Signal Systems applied to biomedical devices including neural interfaces, communication systems, and imaging technology.

3uweeViewNews Object
(
    [_showAnnouncements:protected] => 
    [_showTitle:protected] => 
    [showMore] => 
    [_type:protected] => spotlight
    [_from:protected] => person
    [_args:protected] => Array
        (
            [post_type] => spotlight
            [date_query] => Array
                (
                    [0] => Array
                        (
                            [after] => Array
                                (
                                    [year] => 2015
                                    [month] => 10
                                    [day] => 20
                                )

                        )

                )

            [meta_query] => Array
                (
                    [relation] => AND
                    [0] => Array
                        (
                            [key] => type
                            [value] => news
                            [compare] => LIKE
                        )

                    [1] => Array
                        (
                            [key] => subjects
                            [value] => "895"
                            [compare] => LIKE
                        )

                )

            [posts_per_page] => 6
            [post_status] => publish
        )

    [_jids:protected] => 
    [_taxa:protected] => Array
        (
        )

    [_meta:protected] => Array
        (
            [0] => Array
                (
                    [key] => type
                    [value] => news
                    [compare] => LIKE
                )

            [1] => Array
                (
                    [key] => subjects
                    [value] => "895"
                    [compare] => LIKE
                )

        )

    [_metarelation:protected] => AND
    [_results:protected] => Array
        (
            [0] => WP_Post Object
                (
                    [ID] => 10197
                    [post_author] => 12
                    [post_date] => 2017-03-21 11:33:43
                    [post_date_gmt] => 2017-03-21 18:33:43
                    [post_content] => [caption id="attachment_10198" align="alignleft" width="453"]tong-1 Graduate students Tong Zhang, Ali Najafi, Chenxin Su and Associate Professor Chris Rudell.[/caption]

Nearly all commercial mobile transceivers (cellular phones, WiFi, Bluetooth, etc.) operate in the radio frequency band (1-to-5 GHz [gigahertz]). Due to favorable properties such as the required size of hardware and radio signal propagation loss, the 1-to-5 GHz band is considered the “beachfront real estate” of spectrum allocation. One gigahertz is equal to 1 billion hertz, or one cycle rotation of frequency. Because of this, many U.S. cellular phone carriers pay billions of dollars to acquire a small frequency band of a few megahertz (1 million hertz).

Although the commercial bands are completely occupied by communication applications, including emergency services, Wi-Fi, cellular networks, GPS and Bluetooth devices (as shown in Figure 1), the demand for higher data rates (driven mainly by video) continues with some estimating an increase by as much as 10 times in the next five years.

Electrical engineers in the Future Analog System Technologies (FAST) Lab at the University of Washington, recently demonstrated a novel radio system that uses a new high-frequency integrated CMOS chip and embedded processor. The technique, known as Full Duplex Communication, is capable of operating a single radio’s transmitter and receiver simultaneously, using a single carrier frequency on the same channel (as shown in Figure 2). This allows for better use of the existing commercial radio spectrum.

The UW EE researchers have been investigating Full Duplex Communication for the last five years. The research, which was reported at the 2017 IEEE International Solid-State Circuits Conference (ISSCC) and in a recent paper, set a new world record with respect to linearity, bandwidth and transmitter power output when the radio is used in the full duplex mode. This would allow the radio to operate in full duplex mode over significantly longer distances as compared to prior state-of-the-art. For example, this radio is the first to demonstrate performance potentially compatible with future 5th Generation (5G) wireless standards.

[caption id="attachment_10201" align="alignleft" width="321"]fig1 Figure 1: Federal Communication Commission (FCC) Existing Frequency Allocation in the RF and Sub-Millimeter Wave Bands[/caption]

“Full Duplex Communication has the potential to double the efficiency of spectral use,” said lead author and electrical engineering graduate student Tong Zhang. “It does this by combining the traditional transmit and receive bands into one common frequency channel. This works for any wireless application with two communication, including cellular, Wi-Fi and Bluetooth radios.”

Currently, all radios reduce the possible interaction between a single user’s transmitter (TX) and receiver (RX) by either performing Frequency Domain Duplexing (FDD), which allows a single user to simultaneously transmit on one frequency while receiving a signal on another frequency, or by communicating using Time Division Multiplexing (TDD), where both the transmitter and receiver operate at different times, using different assigned frequencies. Both techniques are used to minimize interference from a given radio’s transmitter to the receiver. By way of example, Verizon phones use an FDD-based system to communicate, while AT&T phones often use TDD. With both FDD and TDD radios, a single user occupies two frequency bands to wirelessly communicate with another radio or base station. In contrast, Full Duplex Communication (as shown in Figure 2) allows a single user’s radio to simultaneously transmit and receive using the same frequency band, thus cutting in half the required frequency allocation of a single transceiver (e.g. a cell phone).

[caption id="attachment_10202" align="alignright" width="328"]Figure 2: Channel Allocation for a Single User (radio) for the case of both traditional (existing) Frequency Division Duplex (FDD) and Future Full-Duplex (FD) Systems.  Figure 2: Channel Allocation for a Single User (radio) for the case of both traditional (existing) Frequency Division Duplex (FDD) and Future Full-Duplex (FD) Systems.[/caption]

“This is analogous to a single lane supporting vehicle traffic in both directions, effectively reducing the needed real estate by half,” said lead faculty and electrical engineering associate professor Chris Rudell. “The obvious challenge of using a single-lane road to support two-way traffic is the potential collision between cars moving in opposite directions. If one radio were to transmit and receive a signal using the same assigned carrier frequency, this leads to a similarly challenging problem of the transmitter presenting interference to its own radio receiver.”

A typical cellular radio may transmit up to 1 Watt of power while very far from the base station, implying that the received signal is very small (as little as a few microvolts [one millionth of a volt] at the antenna). This is shown in Figure 2. Therefore, full duplex radios must supply more than 120 decibels of transmitter self-interference cancellation before the receiver can properly function.

Detecting a weak received radio signal, in the presence of a transmitter blasting at maximum output power, is equivalent to hearing someone whisper from the opposite side of the stadium, over the roar of the crowd, just after a Seahawks touchdown. This demands that the analog, baseband and digital components of the radio achieve sufficient cancellation of the transmitted signal inside the receiver.

[caption id="attachment_10203" align="alignleft" width="365"]Figure 3: Chip Photo of the TSMC 40nm 6L-Metal Prototype Full Duplex Radio Front-end. Figure 3: Chip Photo of the TSMC 40nm 6L-Metal Prototype Full Duplex Radio Front-end.[/caption]

The ISSCC paper describes the high-frequency full duplex radio front-end integrated in an advanced nanometer-length (40nm) Taiwan Semiconductor Manufacturing Company (TSMC) process. The entire full duplex front-end chip (as shown in Figure 3) occupies a die area of less than 4mm2 and includes two self-interference cancellation paths, a frequency synthesizer, analog receiver and a noise canceling power amplifier.

“The Full Duplex Communication transceiver architecture contains a dual-path self-interference cancellation technique, which achieves the state-of-the-art performance,” Zhang said. “The research demonstrates a full radio front-end by complementing the experimental chip with an FPGA to emulate the baseband processor [Figure 4]. The overall embedded radio system self-calibrates the analog dual-path cancellation frontend chip. The configuration works together to develop an efficient method for wireless communication to address future demands for higher data rate”

[caption id="attachment_10204" align="alignright" width="372"]Figure 4:  Measurement Setup of the entire Full Duplex Radio System, which includes the prototype chip and digital baseband emulator (FPGA). Figure 4: Measurement Setup of the entire Full Duplex Radio System, which includes the prototype chip and digital baseband emulator (FPGA).[/caption]

Similar signal processing challenges exist in biological interfaces. At present, the PI and authors of this paper are involved with the Center for Sensorimotor Neural Engineering (CSNE) at the University of Washington, where they are exploring the use of similar full duplex techniques to conquer a longstanding problem with neural interfaces, mainly, the suppression of unwanted stimulation artifacts in the sense (recording) electronics.

Additional co-authors on the paper are electrical engineering graduate students Ali Najafi and Chenxin Su. This research was funded by the National Science Foundation, Google, Qualcomm, Marvell Technology Group and the Center for Design of Analog-Digital Integrated Circuits (CDADIC).
                    [post_title] => UW Radio Researchers Break World Record with Full Duplex Communication
                    [post_excerpt] => 
                    [post_status] => publish
                    [comment_status] => closed
                    [ping_status] => closed
                    [post_password] => 
                    [post_name] => uw-radio-researchers-break-world-record-with-full-duplex-communication
                    [to_ping] => 
                    [pinged] => 
                    [post_modified] => 2017-03-21 11:33:43
                    [post_modified_gmt] => 2017-03-21 18:33:43
                    [post_content_filtered] => 
                    [post_parent] => 0
                    [guid] => http://www.ee.washington.edu/?post_type=spotlight&p=10197
                    [menu_order] => 74
                    [post_type] => spotlight
                    [post_mime_type] => 
                    [comment_count] => 0
                    [filter] => raw
                )

            [1] => WP_Post Object
                (
                    [ID] => 1407
                    [post_author] => 15
                    [post_date] => 2015-12-11 00:58:54
                    [post_date_gmt] => 2015-12-11 00:58:54
                    [post_content] => 
Rajesh Rao Chet Moritz Howard Chizeck Matt Reynolds Smith_Joshua__1457646140_128.95.215.177 Blake Hannaford Chris Rudell Visvesh Sathe
Rajesh Rao Chet Moritz Howard Chizeck Matt Reynolds Joshua Smith Blake Hannaford Chris Rudell Visvesh Sathe
To support the development of implantable devices that can restore movement, and improve the overall quality of life, for people with spinal cord injury or stroke, UW’s Center for Sensorimotor Neural Engineering (CSNE) has received $16 million in funding from the National Science Foundation. The funding, dispersed during the next four years, will allow researchers to continue their cutting-edge work, with the goal of having proof-of-concept demonstrations in humans within the next five years. Based at the UW, the CSNE is directed by EE Adjunct Faculty member Rajesh Rao, who is a UW professor of computer science and engineering. Founded in 2011, the CSNE is one of 17 Engineering Research Centers funded by the National Science Foundation. Core partners are located at the Massachusetts Institute of Technology and San Diego State University. A prime example of cross-campus collaboration, research is being undertaken by a multi-disciplinary team including several UW EE faculty members: Howard Chizeck, Blake Hannaford, Matt Reynolds, Chris Rudell, Visvesh Sathe and Joshua Smith. “UW is extremely fortunate to have visionary leaders in Director Rajesh Rao and Deputy Director Chet Moritz, who are spearheading the cutting edge research at CSNE,” said EE Chair Radha Poovendran. “Under their leadership, the CSNE is growing to be a place where fundamental and translation research for the benefit of society are fostered.” To restore sensorimotor function and neurorehabilitation, CSNE researchers are working to build closed-loop co-adaptive bi-directional brain-computer interfaces that can both record from and stimulate the central nervous system. The devices essentially form a bridge between lost brain connections, achieved by decoding brain signals produced when a person decides they would like to move their arm and grasp a cup. Specific parts of the spinal cord are then stimulated to achieve the desired action. By wirelessly transmitting information, damaged areas of the brain are avoided. Researchers are also working to improve current devices on the market, such as deep brain stimulators that are used to treat Parkinson’s disease. A challenge with current systems is that they are constantly “on” and may provide stimulation to patients when not needed, resulting in unintended side effects as well as reduced battery life. CSNE researchers are working to make these systems "closed-loop," turning them on only when the patient intends to move. See Also: Seattle Times Article UW Today Article [post_title] => CSNE Receives $16 Million to Continue Developing Implantable Devices to Treat Paralysis [post_excerpt] => [post_status] => publish [comment_status] => closed [ping_status] => closed [post_password] => [post_name] => csne-receives-16-million-to-continue-developing-implantable-devices-to-treat-paralysis [to_ping] => [pinged] => [post_modified] => 2016-12-16 15:41:14 [post_modified_gmt] => 2016-12-16 23:41:14 [post_content_filtered] => [post_parent] => 0 [guid] => http://hedy.ee.washington.edu/?post_type=spotlight&p=1407 [menu_order] => 924 [post_type] => spotlight [post_mime_type] => [comment_count] => 0 [filter] => raw ) [2] => WP_Post Object ( [ID] => 784 [post_author] => 15 [post_date] => 2016-01-15 00:23:41 [post_date_gmt] => 2016-01-15 00:23:41 [post_content] => johnsahr_000 Anantram chrisrudell xiaodonghe2 Out of eight newly elected 2016 IEEE Seattle Section Officers, four are UW EE faculty members. Congratulations to Professors John Sahr, M.P. Anantram, Chris Rudell and Affiliate Faculty Member Xiaodong He. The new officers were sworn in on January 12, 2016. More details about each faculty member and their IEEE position are provided below: Professor John Sahr Chapter Chair of Education Professor John Sahr specializes in radar remote sensing of the ionosphere. He and his students developed the first passive bistatic VHF radar for E-region turbulence in 1998, and continue that work today. At the UW, Sahr has served seven years as Associate Dean of Undergraduate Academic Affairs for the entire campus. In this role he acted as the Provost’s representative to Washington State committees that coordinated transfer policy among 2- and 4-year colleges, public and private. He also served 2.5 years as the interim director of the Robinson Center for Young Scholars, the UW’s early entrance program. In 2014, Sahr also served as the Interim Chair of the Department of Electrical Engineering. Professor M.P. Anantram Chapter Chair of Antennas and Propagation/Electron Devices/Microwave Theory Professor M.P. Anantram’s group works on the theory and modeling of nanoscale electronic devices and materials. The current focus is multi-scale modeling of phase change and resistive memory devices, modeling of electron transport in DNA, fast algorithms to calculate Gless and their application to model devices based on two dimensional materials such as graphene and boron nitride. Anantram's prior research included the modeling of nanoscale transistors and carbon nanotube devices. He worked at the NASA Ames Research Center and the University of Waterloo before joining UW. Professor Chris Rudell Chapter Chair of Circuits and Systems Professor Chris Rudell joined the EE department as an Assistant Professor in January 2009. Prior to joining UW EE he was an IC Designer and Project Manager with Delco Electronics (now Delphi); a postdoctoral Researcher at the University of California at Berkeley; an Analog/RF IC Design Engineer at Berkana Wireless (now Qualcomm) in San Jose, California, and later became the Design Manager of the Advanced IC Development Group; and worked in the Advanced Radio Technology Group, at Intel, where his work focused mainly on RF transceiver circuits and systems, in advanced silicon processes. His group's research focuses on a broad range of topics related to analog, mixed-signal, RF and mm-wave circuits. Xiaodong He 2016 Chair of IEEE Seattle Section Affiliate faculty member Xiaodong He is a Senior Researcher in the Deep Learning Technology Center of Microsoft Research, in Redmond, WA. His research interests are mainly in the machine intelligence areas, including deep learning, speech, natural language, computer vision, information retrieval, and knowledge representation and management. He has received several awards including the Outstanding Paper Award of ACL 2015. He is a frequent tutorial and keynote speaker at major conferences in these areas. He and colleagues developed the MSR-NRC-SRI entry and the MSR entry that won No. 1 in the 2008 NIST Machine Translation Evaluation and the 2011 IWSLT Evaluation (Chinese-to-English), respectively, and the MSR image captioning system that won the 1st Prize at the MS COCO Captioning Challenge 2015. [post_title] => Four EE Faculty Elected IEEE Seattle Chapter Officers [post_excerpt] => [post_status] => publish [comment_status] => closed [ping_status] => closed [post_password] => [post_name] => four-ee-faculty-elected-ieee-seattle-chapter-officers [to_ping] => [pinged] => [post_modified] => 2017-06-23 16:36:13 [post_modified_gmt] => 2017-06-23 23:36:13 [post_content_filtered] => [post_parent] => 0 [guid] => http://hedy.ee.washington.edu/?post_type=spotlight&p=784 [menu_order] => 931 [post_type] => spotlight [post_mime_type] => [comment_count] => 0 [filter] => raw ) ) [_numposts:protected] => 6 [_rendered:protected] => 1 [_classes:protected] => Array ( [0] => block--spotlight-tiles ) [_finalHTML:protected] => [_postID:protected] => 895 [_errors:protected] => Array ( ) [_block:protected] => [_db:protected] => WP_Query Object ( [query] => Array ( [post_type] => spotlight [date_query] => Array ( [0] => Array ( [after] => Array ( [year] => 2015 [month] => 10 [day] => 20 ) ) ) [meta_query] => Array ( [relation] => AND [0] => Array ( [key] => type [value] => news [compare] => LIKE ) [1] => Array ( [key] => subjects [value] => "895" [compare] => LIKE ) ) [posts_per_page] => 6 [post_status] => publish ) [query_vars] => Array ( [post_type] => spotlight [date_query] => Array ( [0] => Array ( [after] => Array ( [year] => 2015 [month] => 10 [day] => 20 ) ) ) [meta_query] => Array ( [relation] => AND [0] => Array ( [key] => type [value] => news [compare] => LIKE ) [1] => Array ( [key] => subjects [value] => "895" [compare] => LIKE ) ) [posts_per_page] => 6 [post_status] => publish [error] => [m] => [p] => 0 [post_parent] => [subpost] => [subpost_id] => [attachment] => [attachment_id] => 0 [name] => [static] => [pagename] => [page_id] => 0 [second] => [minute] => [hour] => [day] => 0 [monthnum] => 0 [year] => 0 [w] => 0 [category_name] => [tag] => [cat] => [tag_id] => [author] => [author_name] => [feed] => [tb] => [paged] => 0 [meta_key] => [meta_value] => [preview] => [s] => [sentence] => [title] => [fields] => [menu_order] => [embed] => [category__in] => Array ( ) [category__not_in] => Array ( ) [category__and] => Array ( ) [post__in] => Array ( ) [post__not_in] => Array ( ) [post_name__in] => Array ( ) [tag__in] => Array ( ) [tag__not_in] => Array ( ) [tag__and] => Array ( ) [tag_slug__in] => Array ( ) [tag_slug__and] => Array ( ) [post_parent__in] => Array ( ) [post_parent__not_in] => Array ( ) [author__in] => Array ( ) [author__not_in] => Array ( ) [orderby] => menu_order [order] => ASC [ignore_sticky_posts] => [suppress_filters] => [cache_results] => 1 [update_post_term_cache] => 1 [lazy_load_term_meta] => 1 [update_post_meta_cache] => 1 [nopaging] => [comments_per_page] => 50 [no_found_rows] => ) [tax_query] => WP_Tax_Query Object ( [queries] => Array ( ) [relation] => AND [table_aliases:protected] => Array ( ) [queried_terms] => Array ( ) [primary_table] => wp_posts [primary_id_column] => ID ) [meta_query] => WP_Meta_Query Object ( [queries] => Array ( [0] => Array ( [key] => type [value] => news [compare] => LIKE ) [1] => Array ( [key] => subjects [value] => "895" [compare] => LIKE ) [relation] => AND ) [relation] => AND [meta_table] => wp_postmeta [meta_id_column] => post_id [primary_table] => wp_posts [primary_id_column] => ID [table_aliases:protected] => Array ( [0] => wp_postmeta [1] => mt1 ) [clauses:protected] => Array ( [wp_postmeta] => Array ( [key] => type [value] => news [compare] => LIKE [alias] => wp_postmeta [cast] => CHAR ) [mt1] => Array ( [key] => subjects [value] => "895" [compare] => LIKE [alias] => mt1 [cast] => CHAR ) ) [has_or_relation:protected] => ) [date_query] => WP_Date_Query Object ( [queries] => Array ( [0] => Array ( [after] => Array ( [year] => 2015 [month] => 10 [day] => 20 ) [column] => post_date [compare] => = [relation] => AND ) [column] => post_date [compare] => = [relation] => AND ) [relation] => AND [column] => wp_posts.post_date [compare] => = [time_keys] => Array ( [0] => after [1] => before [2] => year [3] => month [4] => monthnum [5] => week [6] => w [7] => dayofyear [8] => day [9] => dayofweek [10] => dayofweek_iso [11] => hour [12] => minute [13] => second ) ) [request] => SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts INNER JOIN wp_postmeta ON ( wp_posts.ID = wp_postmeta.post_id ) INNER JOIN wp_postmeta AS mt1 ON ( wp_posts.ID = mt1.post_id ) WHERE 1=1 AND ( wp_posts.post_date > '2015-10-20 23:59:59' ) AND ( ( wp_postmeta.meta_key = 'type' AND wp_postmeta.meta_value LIKE '%news%' ) AND ( mt1.meta_key = 'subjects' AND mt1.meta_value LIKE '%\"895\"%' ) ) AND wp_posts.post_type = 'spotlight' AND ((wp_posts.post_status = 'publish')) GROUP BY wp_posts.ID ORDER BY wp_posts.menu_order ASC LIMIT 0, 6 [posts] => Array ( [0] => WP_Post Object ( [ID] => 10197 [post_author] => 12 [post_date] => 2017-03-21 11:33:43 [post_date_gmt] => 2017-03-21 18:33:43 [post_content] => [caption id="attachment_10198" align="alignleft" width="453"]tong-1 Graduate students Tong Zhang, Ali Najafi, Chenxin Su and Associate Professor Chris Rudell.[/caption] Nearly all commercial mobile transceivers (cellular phones, WiFi, Bluetooth, etc.) operate in the radio frequency band (1-to-5 GHz [gigahertz]). Due to favorable properties such as the required size of hardware and radio signal propagation loss, the 1-to-5 GHz band is considered the “beachfront real estate” of spectrum allocation. One gigahertz is equal to 1 billion hertz, or one cycle rotation of frequency. Because of this, many U.S. cellular phone carriers pay billions of dollars to acquire a small frequency band of a few megahertz (1 million hertz). Although the commercial bands are completely occupied by communication applications, including emergency services, Wi-Fi, cellular networks, GPS and Bluetooth devices (as shown in Figure 1), the demand for higher data rates (driven mainly by video) continues with some estimating an increase by as much as 10 times in the next five years. Electrical engineers in the Future Analog System Technologies (FAST) Lab at the University of Washington, recently demonstrated a novel radio system that uses a new high-frequency integrated CMOS chip and embedded processor. The technique, known as Full Duplex Communication, is capable of operating a single radio’s transmitter and receiver simultaneously, using a single carrier frequency on the same channel (as shown in Figure 2). This allows for better use of the existing commercial radio spectrum. The UW EE researchers have been investigating Full Duplex Communication for the last five years. The research, which was reported at the 2017 IEEE International Solid-State Circuits Conference (ISSCC) and in a recent paper, set a new world record with respect to linearity, bandwidth and transmitter power output when the radio is used in the full duplex mode. This would allow the radio to operate in full duplex mode over significantly longer distances as compared to prior state-of-the-art. For example, this radio is the first to demonstrate performance potentially compatible with future 5th Generation (5G) wireless standards. [caption id="attachment_10201" align="alignleft" width="321"]fig1 Figure 1: Federal Communication Commission (FCC) Existing Frequency Allocation in the RF and Sub-Millimeter Wave Bands[/caption] “Full Duplex Communication has the potential to double the efficiency of spectral use,” said lead author and electrical engineering graduate student Tong Zhang. “It does this by combining the traditional transmit and receive bands into one common frequency channel. This works for any wireless application with two communication, including cellular, Wi-Fi and Bluetooth radios.” Currently, all radios reduce the possible interaction between a single user’s transmitter (TX) and receiver (RX) by either performing Frequency Domain Duplexing (FDD), which allows a single user to simultaneously transmit on one frequency while receiving a signal on another frequency, or by communicating using Time Division Multiplexing (TDD), where both the transmitter and receiver operate at different times, using different assigned frequencies. Both techniques are used to minimize interference from a given radio’s transmitter to the receiver. By way of example, Verizon phones use an FDD-based system to communicate, while AT&T phones often use TDD. With both FDD and TDD radios, a single user occupies two frequency bands to wirelessly communicate with another radio or base station. In contrast, Full Duplex Communication (as shown in Figure 2) allows a single user’s radio to simultaneously transmit and receive using the same frequency band, thus cutting in half the required frequency allocation of a single transceiver (e.g. a cell phone). [caption id="attachment_10202" align="alignright" width="328"]Figure 2: Channel Allocation for a Single User (radio) for the case of both traditional (existing) Frequency Division Duplex (FDD) and Future Full-Duplex (FD) Systems. Figure 2: Channel Allocation for a Single User (radio) for the case of both traditional (existing) Frequency Division Duplex (FDD) and Future Full-Duplex (FD) Systems.[/caption] “This is analogous to a single lane supporting vehicle traffic in both directions, effectively reducing the needed real estate by half,” said lead faculty and electrical engineering associate professor Chris Rudell. “The obvious challenge of using a single-lane road to support two-way traffic is the potential collision between cars moving in opposite directions. If one radio were to transmit and receive a signal using the same assigned carrier frequency, this leads to a similarly challenging problem of the transmitter presenting interference to its own radio receiver.” A typical cellular radio may transmit up to 1 Watt of power while very far from the base station, implying that the received signal is very small (as little as a few microvolts [one millionth of a volt] at the antenna). This is shown in Figure 2. Therefore, full duplex radios must supply more than 120 decibels of transmitter self-interference cancellation before the receiver can properly function. Detecting a weak received radio signal, in the presence of a transmitter blasting at maximum output power, is equivalent to hearing someone whisper from the opposite side of the stadium, over the roar of the crowd, just after a Seahawks touchdown. This demands that the analog, baseband and digital components of the radio achieve sufficient cancellation of the transmitted signal inside the receiver. [caption id="attachment_10203" align="alignleft" width="365"]Figure 3: Chip Photo of the TSMC 40nm 6L-Metal Prototype Full Duplex Radio Front-end. Figure 3: Chip Photo of the TSMC 40nm 6L-Metal Prototype Full Duplex Radio Front-end.[/caption] The ISSCC paper describes the high-frequency full duplex radio front-end integrated in an advanced nanometer-length (40nm) Taiwan Semiconductor Manufacturing Company (TSMC) process. The entire full duplex front-end chip (as shown in Figure 3) occupies a die area of less than 4mm2 and includes two self-interference cancellation paths, a frequency synthesizer, analog receiver and a noise canceling power amplifier. “The Full Duplex Communication transceiver architecture contains a dual-path self-interference cancellation technique, which achieves the state-of-the-art performance,” Zhang said. “The research demonstrates a full radio front-end by complementing the experimental chip with an FPGA to emulate the baseband processor [Figure 4]. The overall embedded radio system self-calibrates the analog dual-path cancellation frontend chip. The configuration works together to develop an efficient method for wireless communication to address future demands for higher data rate” [caption id="attachment_10204" align="alignright" width="372"]Figure 4:  Measurement Setup of the entire Full Duplex Radio System, which includes the prototype chip and digital baseband emulator (FPGA). Figure 4: Measurement Setup of the entire Full Duplex Radio System, which includes the prototype chip and digital baseband emulator (FPGA).[/caption] Similar signal processing challenges exist in biological interfaces. At present, the PI and authors of this paper are involved with the Center for Sensorimotor Neural Engineering (CSNE) at the University of Washington, where they are exploring the use of similar full duplex techniques to conquer a longstanding problem with neural interfaces, mainly, the suppression of unwanted stimulation artifacts in the sense (recording) electronics. Additional co-authors on the paper are electrical engineering graduate students Ali Najafi and Chenxin Su. This research was funded by the National Science Foundation, Google, Qualcomm, Marvell Technology Group and the Center for Design of Analog-Digital Integrated Circuits (CDADIC). [post_title] => UW Radio Researchers Break World Record with Full Duplex Communication [post_excerpt] => [post_status] => publish [comment_status] => closed [ping_status] => closed [post_password] => [post_name] => uw-radio-researchers-break-world-record-with-full-duplex-communication [to_ping] => [pinged] => [post_modified] => 2017-03-21 11:33:43 [post_modified_gmt] => 2017-03-21 18:33:43 [post_content_filtered] => [post_parent] => 0 [guid] => http://www.ee.washington.edu/?post_type=spotlight&p=10197 [menu_order] => 74 [post_type] => spotlight [post_mime_type] => [comment_count] => 0 [filter] => raw ) [1] => WP_Post Object ( [ID] => 1407 [post_author] => 15 [post_date] => 2015-12-11 00:58:54 [post_date_gmt] => 2015-12-11 00:58:54 [post_content] =>
Rajesh Rao Chet Moritz Howard Chizeck Matt Reynolds Smith_Joshua__1457646140_128.95.215.177 Blake Hannaford Chris Rudell Visvesh Sathe
Rajesh Rao Chet Moritz Howard Chizeck Matt Reynolds Joshua Smith Blake Hannaford Chris Rudell Visvesh Sathe
To support the development of implantable devices that can restore movement, and improve the overall quality of life, for people with spinal cord injury or stroke, UW’s Center for Sensorimotor Neural Engineering (CSNE) has received $16 million in funding from the National Science Foundation. The funding, dispersed during the next four years, will allow researchers to continue their cutting-edge work, with the goal of having proof-of-concept demonstrations in humans within the next five years. Based at the UW, the CSNE is directed by EE Adjunct Faculty member Rajesh Rao, who is a UW professor of computer science and engineering. Founded in 2011, the CSNE is one of 17 Engineering Research Centers funded by the National Science Foundation. Core partners are located at the Massachusetts Institute of Technology and San Diego State University. A prime example of cross-campus collaboration, research is being undertaken by a multi-disciplinary team including several UW EE faculty members: Howard Chizeck, Blake Hannaford, Matt Reynolds, Chris Rudell, Visvesh Sathe and Joshua Smith. “UW is extremely fortunate to have visionary leaders in Director Rajesh Rao and Deputy Director Chet Moritz, who are spearheading the cutting edge research at CSNE,” said EE Chair Radha Poovendran. “Under their leadership, the CSNE is growing to be a place where fundamental and translation research for the benefit of society are fostered.” To restore sensorimotor function and neurorehabilitation, CSNE researchers are working to build closed-loop co-adaptive bi-directional brain-computer interfaces that can both record from and stimulate the central nervous system. The devices essentially form a bridge between lost brain connections, achieved by decoding brain signals produced when a person decides they would like to move their arm and grasp a cup. Specific parts of the spinal cord are then stimulated to achieve the desired action. By wirelessly transmitting information, damaged areas of the brain are avoided. Researchers are also working to improve current devices on the market, such as deep brain stimulators that are used to treat Parkinson’s disease. A challenge with current systems is that they are constantly “on” and may provide stimulation to patients when not needed, resulting in unintended side effects as well as reduced battery life. CSNE researchers are working to make these systems "closed-loop," turning them on only when the patient intends to move. See Also: Seattle Times Article UW Today Article [post_title] => CSNE Receives $16 Million to Continue Developing Implantable Devices to Treat Paralysis [post_excerpt] => [post_status] => publish [comment_status] => closed [ping_status] => closed [post_password] => [post_name] => csne-receives-16-million-to-continue-developing-implantable-devices-to-treat-paralysis [to_ping] => [pinged] => [post_modified] => 2016-12-16 15:41:14 [post_modified_gmt] => 2016-12-16 23:41:14 [post_content_filtered] => [post_parent] => 0 [guid] => http://hedy.ee.washington.edu/?post_type=spotlight&p=1407 [menu_order] => 924 [post_type] => spotlight [post_mime_type] => [comment_count] => 0 [filter] => raw ) [2] => WP_Post Object ( [ID] => 784 [post_author] => 15 [post_date] => 2016-01-15 00:23:41 [post_date_gmt] => 2016-01-15 00:23:41 [post_content] => johnsahr_000 Anantram chrisrudell xiaodonghe2 Out of eight newly elected 2016 IEEE Seattle Section Officers, four are UW EE faculty members. Congratulations to Professors John Sahr, M.P. Anantram, Chris Rudell and Affiliate Faculty Member Xiaodong He. The new officers were sworn in on January 12, 2016. More details about each faculty member and their IEEE position are provided below: Professor John Sahr Chapter Chair of Education Professor John Sahr specializes in radar remote sensing of the ionosphere. He and his students developed the first passive bistatic VHF radar for E-region turbulence in 1998, and continue that work today. At the UW, Sahr has served seven years as Associate Dean of Undergraduate Academic Affairs for the entire campus. In this role he acted as the Provost’s representative to Washington State committees that coordinated transfer policy among 2- and 4-year colleges, public and private. He also served 2.5 years as the interim director of the Robinson Center for Young Scholars, the UW’s early entrance program. In 2014, Sahr also served as the Interim Chair of the Department of Electrical Engineering. Professor M.P. Anantram Chapter Chair of Antennas and Propagation/Electron Devices/Microwave Theory Professor M.P. Anantram’s group works on the theory and modeling of nanoscale electronic devices and materials. The current focus is multi-scale modeling of phase change and resistive memory devices, modeling of electron transport in DNA, fast algorithms to calculate Gless and their application to model devices based on two dimensional materials such as graphene and boron nitride. Anantram's prior research included the modeling of nanoscale transistors and carbon nanotube devices. He worked at the NASA Ames Research Center and the University of Waterloo before joining UW. Professor Chris Rudell Chapter Chair of Circuits and Systems Professor Chris Rudell joined the EE department as an Assistant Professor in January 2009. Prior to joining UW EE he was an IC Designer and Project Manager with Delco Electronics (now Delphi); a postdoctoral Researcher at the University of California at Berkeley; an Analog/RF IC Design Engineer at Berkana Wireless (now Qualcomm) in San Jose, California, and later became the Design Manager of the Advanced IC Development Group; and worked in the Advanced Radio Technology Group, at Intel, where his work focused mainly on RF transceiver circuits and systems, in advanced silicon processes. His group's research focuses on a broad range of topics related to analog, mixed-signal, RF and mm-wave circuits. Xiaodong He 2016 Chair of IEEE Seattle Section Affiliate faculty member Xiaodong He is a Senior Researcher in the Deep Learning Technology Center of Microsoft Research, in Redmond, WA. His research interests are mainly in the machine intelligence areas, including deep learning, speech, natural language, computer vision, information retrieval, and knowledge representation and management. He has received several awards including the Outstanding Paper Award of ACL 2015. He is a frequent tutorial and keynote speaker at major conferences in these areas. He and colleagues developed the MSR-NRC-SRI entry and the MSR entry that won No. 1 in the 2008 NIST Machine Translation Evaluation and the 2011 IWSLT Evaluation (Chinese-to-English), respectively, and the MSR image captioning system that won the 1st Prize at the MS COCO Captioning Challenge 2015. [post_title] => Four EE Faculty Elected IEEE Seattle Chapter Officers [post_excerpt] => [post_status] => publish [comment_status] => closed [ping_status] => closed [post_password] => [post_name] => four-ee-faculty-elected-ieee-seattle-chapter-officers [to_ping] => [pinged] => [post_modified] => 2017-06-23 16:36:13 [post_modified_gmt] => 2017-06-23 23:36:13 [post_content_filtered] => [post_parent] => 0 [guid] => http://hedy.ee.washington.edu/?post_type=spotlight&p=784 [menu_order] => 931 [post_type] => spotlight [post_mime_type] => [comment_count] => 0 [filter] => raw ) ) [post_count] => 3 [current_post] => -1 [in_the_loop] => [post] => WP_Post Object ( [ID] => 10197 [post_author] => 12 [post_date] => 2017-03-21 11:33:43 [post_date_gmt] => 2017-03-21 18:33:43 [post_content] => [caption id="attachment_10198" align="alignleft" width="453"]tong-1 Graduate students Tong Zhang, Ali Najafi, Chenxin Su and Associate Professor Chris Rudell.[/caption] Nearly all commercial mobile transceivers (cellular phones, WiFi, Bluetooth, etc.) operate in the radio frequency band (1-to-5 GHz [gigahertz]). Due to favorable properties such as the required size of hardware and radio signal propagation loss, the 1-to-5 GHz band is considered the “beachfront real estate” of spectrum allocation. One gigahertz is equal to 1 billion hertz, or one cycle rotation of frequency. Because of this, many U.S. cellular phone carriers pay billions of dollars to acquire a small frequency band of a few megahertz (1 million hertz). Although the commercial bands are completely occupied by communication applications, including emergency services, Wi-Fi, cellular networks, GPS and Bluetooth devices (as shown in Figure 1), the demand for higher data rates (driven mainly by video) continues with some estimating an increase by as much as 10 times in the next five years. Electrical engineers in the Future Analog System Technologies (FAST) Lab at the University of Washington, recently demonstrated a novel radio system that uses a new high-frequency integrated CMOS chip and embedded processor. The technique, known as Full Duplex Communication, is capable of operating a single radio’s transmitter and receiver simultaneously, using a single carrier frequency on the same channel (as shown in Figure 2). This allows for better use of the existing commercial radio spectrum. The UW EE researchers have been investigating Full Duplex Communication for the last five years. The research, which was reported at the 2017 IEEE International Solid-State Circuits Conference (ISSCC) and in a recent paper, set a new world record with respect to linearity, bandwidth and transmitter power output when the radio is used in the full duplex mode. This would allow the radio to operate in full duplex mode over significantly longer distances as compared to prior state-of-the-art. For example, this radio is the first to demonstrate performance potentially compatible with future 5th Generation (5G) wireless standards. [caption id="attachment_10201" align="alignleft" width="321"]fig1 Figure 1: Federal Communication Commission (FCC) Existing Frequency Allocation in the RF and Sub-Millimeter Wave Bands[/caption] “Full Duplex Communication has the potential to double the efficiency of spectral use,” said lead author and electrical engineering graduate student Tong Zhang. “It does this by combining the traditional transmit and receive bands into one common frequency channel. This works for any wireless application with two communication, including cellular, Wi-Fi and Bluetooth radios.” Currently, all radios reduce the possible interaction between a single user’s transmitter (TX) and receiver (RX) by either performing Frequency Domain Duplexing (FDD), which allows a single user to simultaneously transmit on one frequency while receiving a signal on another frequency, or by communicating using Time Division Multiplexing (TDD), where both the transmitter and receiver operate at different times, using different assigned frequencies. Both techniques are used to minimize interference from a given radio’s transmitter to the receiver. By way of example, Verizon phones use an FDD-based system to communicate, while AT&T phones often use TDD. With both FDD and TDD radios, a single user occupies two frequency bands to wirelessly communicate with another radio or base station. In contrast, Full Duplex Communication (as shown in Figure 2) allows a single user’s radio to simultaneously transmit and receive using the same frequency band, thus cutting in half the required frequency allocation of a single transceiver (e.g. a cell phone). [caption id="attachment_10202" align="alignright" width="328"]Figure 2: Channel Allocation for a Single User (radio) for the case of both traditional (existing) Frequency Division Duplex (FDD) and Future Full-Duplex (FD) Systems. Figure 2: Channel Allocation for a Single User (radio) for the case of both traditional (existing) Frequency Division Duplex (FDD) and Future Full-Duplex (FD) Systems.[/caption] “This is analogous to a single lane supporting vehicle traffic in both directions, effectively reducing the needed real estate by half,” said lead faculty and electrical engineering associate professor Chris Rudell. “The obvious challenge of using a single-lane road to support two-way traffic is the potential collision between cars moving in opposite directions. If one radio were to transmit and receive a signal using the same assigned carrier frequency, this leads to a similarly challenging problem of the transmitter presenting interference to its own radio receiver.” A typical cellular radio may transmit up to 1 Watt of power while very far from the base station, implying that the received signal is very small (as little as a few microvolts [one millionth of a volt] at the antenna). This is shown in Figure 2. Therefore, full duplex radios must supply more than 120 decibels of transmitter self-interference cancellation before the receiver can properly function. Detecting a weak received radio signal, in the presence of a transmitter blasting at maximum output power, is equivalent to hearing someone whisper from the opposite side of the stadium, over the roar of the crowd, just after a Seahawks touchdown. This demands that the analog, baseband and digital components of the radio achieve sufficient cancellation of the transmitted signal inside the receiver. [caption id="attachment_10203" align="alignleft" width="365"]Figure 3: Chip Photo of the TSMC 40nm 6L-Metal Prototype Full Duplex Radio Front-end. Figure 3: Chip Photo of the TSMC 40nm 6L-Metal Prototype Full Duplex Radio Front-end.[/caption] The ISSCC paper describes the high-frequency full duplex radio front-end integrated in an advanced nanometer-length (40nm) Taiwan Semiconductor Manufacturing Company (TSMC) process. The entire full duplex front-end chip (as shown in Figure 3) occupies a die area of less than 4mm2 and includes two self-interference cancellation paths, a frequency synthesizer, analog receiver and a noise canceling power amplifier. “The Full Duplex Communication transceiver architecture contains a dual-path self-interference cancellation technique, which achieves the state-of-the-art performance,” Zhang said. “The research demonstrates a full radio front-end by complementing the experimental chip with an FPGA to emulate the baseband processor [Figure 4]. The overall embedded radio system self-calibrates the analog dual-path cancellation frontend chip. The configuration works together to develop an efficient method for wireless communication to address future demands for higher data rate” [caption id="attachment_10204" align="alignright" width="372"]Figure 4:  Measurement Setup of the entire Full Duplex Radio System, which includes the prototype chip and digital baseband emulator (FPGA). Figure 4: Measurement Setup of the entire Full Duplex Radio System, which includes the prototype chip and digital baseband emulator (FPGA).[/caption] Similar signal processing challenges exist in biological interfaces. At present, the PI and authors of this paper are involved with the Center for Sensorimotor Neural Engineering (CSNE) at the University of Washington, where they are exploring the use of similar full duplex techniques to conquer a longstanding problem with neural interfaces, mainly, the suppression of unwanted stimulation artifacts in the sense (recording) electronics. Additional co-authors on the paper are electrical engineering graduate students Ali Najafi and Chenxin Su. This research was funded by the National Science Foundation, Google, Qualcomm, Marvell Technology Group and the Center for Design of Analog-Digital Integrated Circuits (CDADIC). [post_title] => UW Radio Researchers Break World Record with Full Duplex Communication [post_excerpt] => [post_status] => publish [comment_status] => closed [ping_status] => closed [post_password] => [post_name] => uw-radio-researchers-break-world-record-with-full-duplex-communication [to_ping] => [pinged] => [post_modified] => 2017-03-21 11:33:43 [post_modified_gmt] => 2017-03-21 18:33:43 [post_content_filtered] => [post_parent] => 0 [guid] => http://www.ee.washington.edu/?post_type=spotlight&p=10197 [menu_order] => 74 [post_type] => spotlight [post_mime_type] => [comment_count] => 0 [filter] => raw ) [comment_count] => 0 [current_comment] => -1 [found_posts] => 3 [max_num_pages] => 1 [max_num_comment_pages] => 0 [is_single] => [is_preview] => [is_page] => [is_archive] => 1 [is_date] => [is_year] => [is_month] => [is_day] => [is_time] => [is_author] => [is_category] => [is_tag] => [is_tax] => [is_search] => [is_feed] => [is_comment_feed] => [is_trackback] => [is_home] => [is_404] => [is_embed] => [is_paged] => [is_admin] => [is_attachment] => [is_singular] => [is_robots] => [is_posts_page] => [is_post_type_archive] => 1 [query_vars_hash:WP_Query:private] => 52c0bf04fbd357771bf3621e22dcd185 [query_vars_changed:WP_Query:private] => 1 [thumbnails_cached] => [stopwords:WP_Query:private] => [compat_fields:WP_Query:private] => Array ( [0] => query_vars_hash [1] => query_vars_changed ) [compat_methods:WP_Query:private] => Array ( [0] => init_query_flags [1] => parse_tax_query ) ) )
 

Representative Publications

  • T. Zhang, A.R. Suvarna, V. Bhagavatula and J.C. Rudell, “An Integrated CMOS Passive Self-Interference Mitigation Technique for FDD Radios," Proc. IEEE J. Solid-State Circuits, vol. 50, pp. 1176-1188, May, 2015.
  • A High-Voltage Compliant Neural Stimulator With HF Wireless Power and UHF Backscatter Communication, Vaishnavi Ranganathan, Brody Mahoney, Eric Pepin, Michael Sunshine, Chet T. Moritz, Jacques C. Rudell, Joshua R. Smith, IEEE WPTC, 2016.
  • V. Bhagavatula, W. Wesson, S. Shin and J. Rudell, “A Fully-Integrated, Regulator-less CMOS Power Amplifier for Long-Range Wireless Sensor Communications,” Proc. IEEE J. Solid-State Circuits, vol. 48, pp. 1225-1236, May, 2013.
  • E. Pepin, J. Uehlin, D. Micheletti, S.I. Perlmutter, J.C. Rudell, “A High-Voltage Compliant, Electrode-Invariant Neural Stimulator Front-End in 65nm Bulk-CMOS,” at IEEE European Solid-State Circuits Conf., Lausanne, CH, 2016.
  • V. Bhagavatula, M. Taghivand and J.C. Rudell, “A compact 77% fractional bandwidth CMOS band-pass distributed with mirror-symmetric Norton transforms,” Proc. IEEE J. Solid-State Circuits, vol. 50, pp. 1085-1093, May, 2015.
  • V. Bhagavatula, T. Zhang, A.R. Suvarna and J.C. Rudell, “An ultra-wideband millimeter-wave heterodyne receiver with a 17-GHz IF channel bandwidth using gain-equalized transformers,” Proc. IEEE J. Solid-State Circuits, vol. 51, pp. 323-331, Feb., 2016.

Associated Labs

Research Areas

Affiliations

Education

  • Ph.D. Electrical Engineering
    University of California, Berkeley
  • M.S. Electrical Engineering
    University of California, Berkeley
  • B.S. Electrical Engineering
    University of Michigan, Ann Arbor