P.A. Rolland

Pulse to Pulse Stability of Solid State Transmitter Module for Radars Application

Pulse to pulse stability, an important characteristic of transmitter radar is characterized by the level of phase and amplitude variation between successive pulses of a burst of microwave signal. This variation of phase and amplitude determines directly detection limit of targets with very low RCS in presence of sub-clutter. Pulse to pulse instability can be related to external or intrinsic causes. This characteristic has to be quantified for all radar transmitter. For that, several methods can be used : Two temporal methods (standard deviation and rms method), and a spectral method. In order to characterize solid state module pulse to pulse stability, we have designed a specific test bench. This article describes the capabilities and gives a lot of significant results and performance of solid state module we have produced in our microwave laboratory of THOMSON-CSF AIRSYS and of this test bench.

60 GHz UWB-IR Transceiver With Pulsed-Injected Locked Oscillator

A simple but efficient transceiver for UWB Impulse Radio (UWB-IR) signal generation in millimeter-wave band for Giga-bit WLAN is presented. The emitter involves a subharmonic Injection Locked Oscillator (ILO) driven by a pulse generator with fast transition time. Its frequency oscillation is locked to one of the numerous harmonic components of the pulse generator at 30 GHZ, which permits to obtain a stable pulse to pulse phase condition. The start of the oscillations is studied, using the external quality factor Qext as main factor. Then a frequency doubler permits this modulated signal to be transposed at 60 GHz. The receiver includes a LNA, a RF-detector and a UWB Sample and Hold Amplifier (SHA). Some MMIC have been designed using a commercial pHEMT foundry process (ft = 100 GHz=): a pulse generator exhibiting less than 25 ps transition times, an oscillator with a 30 GHz free running output frequency, a LNA, a MPA, a RF detector at 60 GHz and a UWB SHA.

Design of a fully HBT 40GS/s sampling circuit for very large bandwidth non repetitive signal analysis

The design of a fully heterojunction bipolar transistor (HBT) circuit allowing 20GHz bandwidth random signal sampling and the experimental results of the basic circuits are discussed. Assuming a temporal analysis depth of 5ns, this circuit, based on the principle of non simultaneous spatial sampling can reach, in a single shot mode, a truly sampling frequency of 40GS/s. Its realization, led through several InP HBT MMIC (F/sub T/=180GHz) and CPW propagation line permits to meet the main requirements in terms of bandwidth, dynamic range and jitter.

A combined ASK-PPM Time Hopping UWB transceiver for millimetre wave Gigabit WLAN

A simple but efficient architecture based on up-conversion of impulse radio (IR) signals at 55 GHz is presented. This complete architecture has been designed using a pHEMT foundry process (ft =100 GHz). Key results on mm-waves devices-VCO, frequency doubler, RF switch, LNA and RF detector-are presented and discussed. Baseband devices, composed of a pulse generator and a sample-and-hold amplifier, are also presented with experimental results. These results show our fully monolithically integrated demonstrator performs PPM time hoping and ASK modulation schemes with respective data rate up to 500 Mbps and 1 Gbps

Jitter analysis of electrical samplers based on a propagation line

The aim of this paper is to demonstrate the good jitter performances of samplers based on a propagation line. Targeting high resolution and high bandwidth (10 effective bits at 8 GHz and 20 GHz bandwidth) two of these architectures have been adapted to large temporal sampling windows. As the trigger structures consist of inverters, the jitter of an elementary inverter is optimized and a delay cell is simulated and compared to measurements Jilter of the two trigger structures is discussed.temporal sampling windows.

Solid-state 8 GHz transient signal digitizer characterization

A new technique leading to an accurate sampling of single shot high frequency signals is described. This technique provides 20 GHz sampling of electrical pulses up to 8 GHz bandwidth with a 60 dB dynamic range. The prototype of a transient digitizer involving this new principle is tested, with the goal of a new product development. We present the theory of the sampling operations, the outline of the prototype, the design and fabrication of an innovative set of specific GaAs MMICs, the assembling of the complete system and the first results obtained in performance characterization.

20GHz bandwidth digitizer for single shot analysis

The design of a single shot sampling circuit allowing 20GHz bandwidth random signal and the experimental results of the main circuits are described. Assuming a temporal analysis depth of 5ns, this circuit, based on the principle of non simultaneous spatial sampling and realized in InP HBT MMIC (FT=180GHz) and CPW propagation line, can reach a truly sampling frequency of 40GS/s. Very good performances are expected using such a technology in terms of bandwidth, dynamic range and jitter. Moreover a specific test bench allowing very low jitter measurement is presented

InP DHBT based MMICs for [DC-20 GHz] Signal Sampling

Targeting [DC-20 GHz] bandwidth and 40 GS/s sampling rate for high dynamic range (60 dB) ultra fast signal analysis, we present the preliminary experimental results obtained on InP-InGaAs-InP double heterojunction bipolar transistor based MMIC (FT = 180 GHz). The critical circuits leading to wide band signal sampling operation are made of high bandwidth switched emitter follower (SEF) and high bandwidth buffer. They are realized and tested both in time and frequency domains. They exhibit performances in terms of isolation and bandwidth compatible with the targeted objectives

Optimum Design of CW 94 GHz Si DDR IMPATT Sources

This paper describes a theoretical and experimental approach to design optimum high power high efficiency CW IMPATT sources in the 94 GHz window. Particular emphasis is placed on junction temperature rise in order to achieve reliable high power operation. Secund order parameters such as noise and locking bandwidth are also considered.