MRI & NMR spectrometer

Transcription

1 AMOS MRI & NMR spectrometer The AMOS Spectrometer is a highly modular and flexible unit that provides the ability to customize synchronized configurations for preclinical and clinical MR applications. The AMOS Spectrometer has an exceptional robust and flexible configuration, allowing the addition of RF Tx / RF Rx / Gradient channels to an existing unit, or the addition of fully synchronized units. The AMOS Spectrometer utilizes innovative, state-of-the-art Analog and Digital technologies to provide the highest performance on the market today. This advanced unit features unique capabilities and can be fitted as an upgrade to any existing MRI or NMR system to enhance its performance and features.

2 Main features: Fully digital receive and transmit channels, implemented by FPGA and 250 MHz signal sampling. The advantages of this design include superior synchronization between receive and transmit channels and no intermediate frequency conversion and bandwidth support up to 12T (> 511MHz, with the addition of the Aspect MR Frequency Expander unit). Flexible configuration The basic AMOS unit casing is a 19" 4U chassis that can be populated in four slots. Each slot can be populated either by a single RF transmitter and a single RF receiver, and three gradient channels, OR four RF Receive channels. A wide range of MR system configurations can be addressed by the AMOS Spectrometer that enables the connection of up to 8 AMOS units to work together while maintaining superior synchronization. Compact configuration - a unique option of 1U chassis with the basic single slot. Main functions Full chassis parallelization capability for large-scale receive and transmit channels. Frequency range: o 4-86 MHz o And up to 12T (> 511MHz, with the addition of the Aspect MR Frequency Expander unit) Each FID is available immediately after it is acquired - There is no need to wait for the end of the scan. This allows dynamic control over scan parameters, evolving reconstruction and sophisticated image enhancement techniques. Flexible hardware - embedded digital filters for optimal signal to noise ratio. Up to 500 MB waveform memory built in the system. Gradient X, Y, Z analog and digital outputs. Internal loopback testing capability, thus allowing automatic testing of all sub-components. Intuitive and flexible user interface for pulse sequences programing. Gradient Monitor - sampling the actual gradient currents for automatic compensation of Eddy currents.

3 Imaging quality samples

4 Open source pulse programming Open source pulse programming language and hardware support the following: C# programming with debugging capability - allows minimal start-up time for pulse sequence programmers Arbitrary number of nested loops - provides programming flexibility Branching - provides program flexibility Real-time capability - scan parameters can be dynamically changed during the scan thus allowing compensation for frequency drift in magnets Rollback of loop indices - prevents perturbations originating from intermittent interferences by rescanning lines in K-space which were affected by the interference Sequences are visualized - using a uniform physical time scale to simplify reviewing the pulse sequence Main modules (boards) and configuration: Tx board First type of Analog front end board supporting single RF transmitter, single RF receiver, three gradient controls, and three gradient monitor channels. o Transmitter - Converts the pulse sequence digital signal into Analog RF signals at frequencies of 4MHz to 86MHz (and > 511MHz, with the addition of the Aspect MR Frequency Expander unit) o Receiver Amplifies the analog RF signals coming from the MRI system Pre-Amplifier in the frequency band of 4MHz to 86MHz (and > 511MHz, with the addition of the Aspect MR Frequency Expander unit) and then convert them to a digital data stream with minimal distortion and degradation of SNR o Gradients Control - Converts the digital Gradient Amplifier demand signal into an analog signal o Gradients Monitor - Converts the Gradient output analog sample signal into a digital stream 4Rx board Second type of Analog board supporting four RF receiver channels. The 4Rx board amplifies the four analog RF signals coming from the MRI system Pre-Amplifier, in the frequency band of 4MHz to 86MHz (and > 511MHz, with the addition of the Aspect MR Frequency Expander unit) and converts them to a digital data stream with minimal distortion and degradation of SNR.

5 Interface I/Os: General purpose I/O connector Sync IN connector Sync OUT connector RF Transmission port/s RF Reception port/s Analog Gradient outputs Analog Gradient monitor inputs Digital Gradient outputs Ethernet capabilities The AMOS Spectrometer has two physical ports for communicating with a Host Computer: Gigabit Ethernet over copper Gigabit Ethernet over fiber Triggering Various inputs and outputs of trigger signals are supported by the AMOS Spectrometer, used for Scan synchronization. Interface between multiple amos units In systems that use multiple AMOS Spectrometers (as in the below example), there is a synchronization interface between the AMOS master system and the AMOS slave systems. They are: Ref in & Ref out signals for clock synchronization Sync_in, Sync_out Synchronizes for data synchronization Example: Interface between multiple AMOS units

6 Technical specifications Digital receiver Bandwidth Maximum input power Signal to noise ratio before windowing (over the entire 4-86 MHz Frequency range) Noise figure Input RL Flatness Gain capability Aliasing rejection Clock frequency stability 4 MHz- 86 MHz (up to 12T upon request (> 511MHz)) < 10 dbm > 65 db < 4 db > 15 db < 0.03 db over 1MHz BW > 40 db > 80 db < 10 PPB Digital transmitter Maximum output power Output RL Timing resolution Bandwidth Control over amplitude, frequency, and phase Gain control resolution Frequency control resolution Phase control resolution Flatness OIP3 Spurious (over the entire BW) Noise figure AM-AM over upper 40 db AM-PM over upper 40 db 6 ±1 dbm > 15 db 4 nsec 4 MHz- 86 MHz (up to 12T upon request) 0.1 db steps over 60 db < 0.1 Hz step < degree step < 0.07 db over 1 MHz bandwidth > 35 dbm > 72 dbc < 9 db < 0.1 db < 2 degrees

7 Gradients 3x Differential output ±10V, 20 bit 1MSamples/Sec Bandwidth < 200 KHz Full data flow implemented using 32 bit floating point format, including: Wave data, Oblique calculation, Configurable and dynamic gain calculation, Shim, Pre-emphasis Up to 32M points (floating point format) per gradient channel Digital communication to compatible gradient amplifiers 3x Gradient Monitor Inputs: Single ended ±10V input, 16-bit resolution; Allows time-accurate, simultaneous monitoring of all gradient currents through sequence programming Digital input and output lines Unblank output signal per transmit channel (up to 4 channels), 2.5V LVCMOS Pre-Tx output signal per transmit channel (up to 4 channels), 2.5V LVCMOS Two software configurable test points 4 external input triggers, software configurable in pulse sequence, allowing to trigger pulse sequence events to external triggers (e.g. ECG) 8 general use input/output signals, Input 5V tolerant LVCMOS 2.5V, Output 2.5V LVCMOS Synchronization between channels and between units 10 MHz low jitter OCXO reference clock used to synchronize all transmit and receive channels in a spectrometer unit 10 MHz low jitter OCXO reference clock used to synchronize spectrometer units, allowing chaining up to 8 units Power rating VAC, 3A, 50/60 Hz Safety and emc compliance Safety certification IEC , 3rd edition, ES (2012) CAN/CSA-C22.2 NO EMC certification IEC , 3rd edition, FCC - 47 CFR part 18 RoHS compliance Complies with 2011/65/EU (RoHS 2)

8 DOC Rev.1 Specifications are subject to change without notice. Aspect Imaging 2016.