16 documents found, page 1 of 2
Circuito de Compensação de Junção Fria para Termopar
Brito, Fábio; Barata, Rui; Velez, Fernando J.; Reis, António D.Este documento tem como objetivo testar a efetividade prática de um circuito de condicionamento de sinal de um sensor de temperatura, nomeadamente um termopar. Antes de adquirir o sinal de um sensor para digitalização, um dos requisitos no condicionamento de sinal, consiste na implementação de um circuito de compensação de junção fria, para a obtenção mais precisa do valor de tensão obtido. O termopar permite m...
Impact of the noise spikes on sequential symbol synchronizers
Reis, António D.; Rocha, José F.; Gameiro, Atílio S.; Carvalho, José P.This work study the impact of the noise spikes on sequential symbol synchronizers. We distinguish two synchronizers variants which are: the one that processes the both data transitions and the one thatprocess only the positive data transition. In each one, weconsider two versions namely the manual and the automatic. The objective is to study the various synchronizers outputjitter UIRMS (Unit Interval Root Mean ...
Four carrier phase synchronizers tested with three input waves
Reis, António D.; Rocha, José F.; Gameiro, Atilio S.; Carvalho, José P.In this work, we will study four carrier phase synchronizer types namely the analog, the hybrid, the combinational and the sequential. The four carrier phase synchronizers will be operated firstwith the sinusoidal wave, after with the triangular wave andlast with the rectangular wave. The main objective is to study the four synchronizer types with the three input waves and to observe its jitter UIRMS(Unit Inter...
Four symbol phase synchronizers tested with three input sequences
Reis, António D.; Rocha, José F.; Gameiro, Atilio S.; Carvalho, José P.This work study four symbol synchronizers namely the analog, hybrid, combinational and sequential. These four synchronizers will be tested with three differentinput sequences (P1, P2 and P7). P1=21 (1one-1zero 1-0) isdeterministic, P2=22 (2ones-2zeros 11-00) is deterministicand P7=27-1 (1 ... 0) is pseudo - random. The objective is to study the four synchronizers and toevaluate their jitter UI-RMS (Unit Interva...
A new process to measure the jitter of a system
Reis, António D.; Rocha, José F.; Gameiro, Atilio S.; Carvalho, José P.This work presents a new process to measure the signal jitter, caused by noise, in a communication system. First, we show some conventional jitter measurers and afterwe present the new proposed process. We will test the newjitter measurer on the analog PLL (Phase Lock Loop). The objective is to certify the new process, showing that theresults obtained with it are coherent with the theoretical andexperimental va...
Sequential synchronizers with the pulse comparation and clock sampling variants
Reis, António D.; Rocha, José F.; Gameiro, Atilio S.; Carvalho, José P.The function of the synchronizer is to sample the data with the minimum bit error rate (BER) and to retime its bit duration with the original format. In this work, we present the sequential synchronizer with two variants which are the pulse comparation discovered by Hogge and the clock sampling discovered by us. Each variant has two versions which are the manual and the automatic. The main objective is to study...
Deterministic wave and random symbol phase digital synchronizers
Reis, António D.; Rocha, José F.; Gameiro, Atilio S.; Carvalho, José P.In this paper, we present two groups of synchronizers: the Deterministic Wave Phase Digital Synchronizer and the Random Symbol Phase Digital Synchronizer.In the first case, the VCO (Voltage Controlled Oscillator)synchronizes with the deterministic phase of the input regularwave and in the second the VCO synchronizes with the random phase of the input random symbols. In each one of this groups, we present two di...
Systems of synchronous and asynchronous communication
Reis, António D.; Rocha, José F.; Gameiro, Atílio S.; Carvalho, José P.The communication systems has two different types, namely the synchronous type and the asynchronous type. In the synchronous type the emitter and receiver clocks are in perfect synchronism, therefore they are rigorously equals and dependents. However, in the asynchronous type the emitter and receiver clocks are not in perfect synchronism, therefore they can be slightly different and independents. Our main objec...
Wave and symbol synchronizers
Reis, António D.; Rocha, José F.; Gameiro, Atilio S.; Carvalho, José P.In this paper we present four wave synchronizers and four symbol synchronizers: analog, hybrid, combinational and sequential. All them are of the class closed loop. The wave synchronizers are vacated to synchronize withwaves or signals with deterministic phase/transition. The symbol synchronizers are vacated to synchronize withsymbols or signals with random phase/transition. The main objective is to study and c...
Asynchronous capacities of the sequential symbol synchronizer
Reis, António D.; Rocha, José F.; Gameiro, Atilio S.; Carvalho, José P.In this paper we present four types of normal symbol synchronizers, namely the analog, the hybrid, the combinational and the sequential.The synchronous sequential synchronizer has capacities that permits to obtain the correspondent asynchronous version.So the fiip flop is substituted by logic with feedback. Then all the synchronizers use only logic gates.The main objective is to develop the synchronous sequenti...