Design of front end of a RF receiver

Radio frequency (RF) circuit is having a rapid growth in wireless telecommunication. The increasing demand for higher quality and popularity of wireless services have urged the development of low cost multi-functional and reconfigurable RF front end modules fabricated from advanced device technologies. The RF front end is generally defined as everything between antenna and the intermediate frequency (IF) stage. For a receiver, this "between" area in eludes filter, low noise amplifier, mixer and local oscillator. The circuit was designed based on CMOS 0.18 um technology to input a 2. 5 GHz RF signal and local oscillation of 2.25 GHz. This results in an output IF frequency of 250 MHz. The RF front end circuit had been simulated using Advanced Design System to obtain the proper output frequency and determining the system performance

Low power BPSK modulator for the application of capsule endoscope

This paper presents the Binary Phase Shift Keying (BPSK) modulator for high data rate medical imaging for capsule endoscope. The BPSK modulator consists of a mixer and a ring oscillator. The ring oscillator provides carrier frequency of 433MHz and mix with the mixer to produce BPSK modulated signal. The modulator is designed using Silterra 0.13μm CMOS process. For supply voltage of 1.2 V, data rate of 3.5Mbps the mixer has power consumption of 1.2mW and at output power of -10.7 dBm

Low power modulator for the application of capsule endoscope

This paper presents the radio frequency (RF) modulator for high data rate medical imaging for capsule endoscope. The RF modulator consists of a mixer and a ring oscillator. The ring oscillator provides carrier frequency of 433MHz and mix with the mixer to produce modulated signal. The modulator is designed using Silterra 0.13μm CMOS process. For supply voltage of 1.2 V, data rate of 3.5Mbps the mixer has current consumption of 594μA, IIP3 of 2dBm and at output power of -14.6 dBm. The ring oscillator consumes 740μA with phase noise of -81 dBc/Hz @ 160kHz offset

Low power transmitter for wireless capsule endoscope

This paper presents the transmitter circuit designed for the application of wireless capsule endoscope to overcome the limitation of conventional endoscope. The design is performed using CMOS 0.13 μm technology. The transmitter is designed to operate at centre frequency of 433.92 MHz, which is one of the ISM band. Active mixer and ring oscillator made up the transmitter and it consumes 1.57 mA of current using a supply voltage of 1.2 V, brings the dc power consumption of the transmitter to be 1.88 mW. Data rate of 3.5 Mbps ensure it can transmit high quality medical imaging

Low power transmitter for capsule endoscope

This chapter presents the design technique of low power transmitter for the medical application of capsule endoscope. Considering the loss against frequency in a body wireless communication, ISM band of 434 MHz is employed in the design of the transmitter. This band has lower loss and relatively higher data rate compared to other standards. Inductorless architecture was adopted in the circuit design to reduce the circuit area, thus contribute to the reduction of capsule size.The core component of transmitter, the up-conversion mixer and ring oscillator is designed using CMOS 0.13μm technology with voltage supply of 1.2 V. Both the mixer and ring oscillator consumes 1.57 mA of current, brings the dc power consumption of the transmitter to be 1.88 mW. Data rate of 3.5 Mbps ensure it can transmit high quality medical imaging. The proposed up-conversion and ring oscillator achieved low power and less area while still having the good performance. This achievement makes circuit integration for low power transmitter realizable

Development of CMOS imager block for capsule endoscope

This paper presents the development of imager block to be associated in a capsule endoscopy system. Since the capsule endoscope is used to diagnose gastrointestinal diseases, the imager block must be in small size which is comfortable for the patients to swallow. In this project, a small size 1.5V button battery is used as the power supply while the voltage supply requirements for other components such as microcontroller and CMOS image sensor are higher. Therefore, a voltage booster circuit is proposed to boost up the voltage supply from 1.5V to 3.3V. A low power microcontroller is used to generate control pulses for the CMOS image sensor and to convert the 8-bits parallel data output to serial data to be transmitted to the display panel. The results show that the voltage booster circuit was able to boost the voltage supply from 1.5V to 3.3V. The microcontroller precisely controls the CMOS image sensor to produce parallel data which is then serialized again by the microcontroller. The serial data is then successfully translated to 2fps image and displayed on computer

高速ラテラル電界制御型電荷変調素子を用いた誘導ラマン散乱CMOSイメージセンサに関する研究

博士(工学)doctoral創造科学技術大学院静岡大学甲第920号ET

Low power modulator for capsule endoscope

The evolution of wireless communication and circuit integration has brought medical science and devices to a new dimension. This leads to the invention of wireless capsule endoscope. Conventional endoscope for gastrointestinal diseases diagnoses which are uncomfortable for patients, have certain limitations in performing diagnosis or treatment. Thus it is not feasible for the conventional endoscope, in terms of travelling through a long and convoluted small intestine. Wireless capsule endoscopy addresses the disadvantages of the conventional wired endoscopes where it can reach the small intestine and achieve diagnosis without discomforting the patients as well as easily travel through the digestion tract. Being a wireless device, the design of the capsule endoscope transmitter is paramount for the overall performance. Power consumption is the utmost important aspect in the consideration. The selection of the standard or carrier frequency is optimum to ot requirements which are image quality and frame rate. Considering the loss against frequency in a human body wireless communication, Industrial, Scientific, Medical (ISM) band of 434 MHz is employed in the design of the transmitter. This band has lower loss and relatively higher data rate compared to other standards. Inductorless architecture was adopted in the circuit design to reduce the circuit area, thus contribute to the reduction of capsule size. Taking into account on the aspects in concern, the up-conversion mixer, ring oscillator and the integrated modulator is designed using CMOS 0.13 μm technology with voltage supply of 1.2 V. Low power consumption is achieved where the mixer consumes only 594 uA, which is equivalent to 712.8 uW of power consumption. Positive linearity is achieved with Third-Order Intercept Point (IIP3) of 2 dBm, while the dynamic range which is represented by P1dB is -5.43 dBm. Noise figure of the mixer is found to be 23 dB. The ring oscillator consumes 740 μA which translate to 888 μW of power consumption. Phase noise achieved is -81 dBc/Hz at 160 kHz of offset frequency. The integrated modulator achieves power consumption of 1.88 mW,which is superior compared to other reported work. Battery life utilizing the proposed architecture can reach 13.8 hours compared to the average of 8 hours operational time. Die area utilized is merely 0.44 mm2 which allows better integration of other blocks in the capsule endoscope

Label-Free Biomedical Imaging Using High-Speed Lock-In Pixel Sensor for Stimulated Raman Scattering

Raman imaging eliminates the need for staining procedures, providing label-free imaging to study biological samples. Recent developments in stimulated Raman scattering (SRS) have achieved fast acquisition speed and hyperspectral imaging. However, there has been a problem of lack of detectors suitable for MHz modulation rate parallel detection, detecting multiple small SRS signals while eliminating extremely strong offset due to direct laser light. In this paper, we present a complementary metal-oxide semiconductor (CMOS) image sensor using high-speed lock-in pixels for stimulated Raman scattering that is capable of obtaining the difference of Stokes-on and Stokes-off signal at modulation frequency of 20 MHz in the pixel before reading out. The generated small SRS signal is extracted and amplified in a pixel using a high-speed and large area lateral electric field charge modulator (LEFM) employing two-step ion implantation and an in-pixel pair of low-pass filter, a sample and hold circuit and a switched capacitor integrator using a fully differential amplifier.A prototype chip is fabricated using 0.11 m CMOS image sensor technology process. SRS spectra and images of stearic acid and 3T3-L1 samples are successfully obtained. The outcomes suggest that hyperspectral and multi-focus SRS imaging at video rate is viable after slight modifications to the pixel architecture and the acquisition system