Codex Corporation

About: Codex Corporation is a based out in . It is known for research contribution in the topics: Network packet & Signal. The organization has 189 authors who have published 241 publications receiving 32205 citations.

Signal structures for double side band-quadrature carrier modulation

Abstract: Double side band-quadrature carrier modulation signal points as mapped on the complex plane are drawn from an alphabet consisting of at least 8 points, and are set up in concentric rings each rotated by 45° with respect to adjacent rings. Differential encoding is shown encoding the phase components of the transmitted signals.

Digital modem transmitter

Abstract: A data modulator for transmitting a first sequence of data symbols at a symbol rate of 1/T, the modulator being characterized as having a carrier frequency of f c Hz and the data symbols being denoted as x(kT), where x(kT) is a real or complex number and k is the time index of the kth symbol, featuring, in one aspect, modulated signal generating means for receiving the first sequence and generating, in response thereto and at the symbol rate, a second sequence of complex-valued signals y(kT), the signal y(kT) representing the complex number y(kT)=x(kT)·exp (j2πf c kT), where j=√-1, and filter means for receiving the second sequence and generating, in response thereto, a third sequence of real-valued signals, at a rate higher than the symbol rate, the third sequence representing linear combinations of the real and imaginary parts of the second sequence of complex-valued signals y(kT).

Arbitration among multiple users of a shared resource

Abstract: Arbitration is performed among a plurality of users (12a-12n) for access to a shared resource in a system (10) of the kind in which the users (12a-12n) arbitrate by placing arbitration signals on a line (19) and subsequently comparing their arbitration signals with a signal appearing on the line (19), by providing the users (12a-12n) with independently operating clocks (18) and controlling the progression of the arbitration based on timing provided by the clock (18) of at least one of the users (12a-12n). The progression of the arbitration thus does not depend upon a single master clock, or upon synchronizing the individual user clocks (18). Users that request access are assigned a first priority in the arbitration based at least on an access priority preassigned to the request for access and on whether the user is a member of a current group of users that is formed at a time during the arbitration when another group of users is empty, the current group including users that have been denied access as of that time; at least a portion of each user's arbitration signal is arranged as a multibit word having a value that represents the first priority, and each user that arbitrates for access places its multibit word in parallel on the path and determines whether it has won the arbitration by subsequently comparing its multibit word value with the value of a multibit word that appears on the path.

Network data flow control technique

Abstract: Data flow in a communications network is controlled by a downstream node specifying the maximum average speeds of a plurality of data streams sent from an upstream node on a plurality of data paths.

Device and method for asynchronous cyclic redundancy checking for digital receivers

Abstract: A device and method for asynchronous cyclic redundancy checking (CRC) for digital receivers includes utilizing a finite impulse response (FIR) filter, and comparing and gating circuits. The FIR filter may contain a first multiple delay system unit (102) and a first logic gating system (104). The comparing and gating circuit may contain a second multiple delay system unit (106), and a second logic gating system (110). The device and method is implementable, where desired, utilizing a computer program. The invention provides a faster determination of a CRC frame synchronization on a received digital signal.