Frame synchronization for asynchronous transmission
First Claim
Patent Images
1. A method for transmission of a digital information packet, the method comprising the steps of:
- transmitting a synch word of a packet header of said packet from a transmitter to a receiver over a distorting channel, transmission of said synch word being interrupted by at least one bit time of quiescence of the transmitter; and
at said receiver, receiving said synch word and based on a channel distortion characteristic determined for said received synch word, determining a preferred sampling point for succeeding bits of said packet.
5 Assignments
0 Petitions
Accused Products
Abstract
A method for transmission of a digital information packet. A synch word of a packet header of the packet is transmitted from a transmitter to a receiver over a distorting channel. During transmission of the synch word, transmission is interrupted by at least one bit time of quiescence of the transmitter. The synch word is received at the receiver. Based on a channel distortion characteristic determined for the received synch word, a preferred sampling point is determined for succeeding bits of the packet.
-
Citations
18 Claims
-
1. A method for transmission of a digital information packet, the method comprising the steps of:
-
transmitting a synch word of a packet header of said packet from a transmitter to a receiver over a distorting channel, transmission of said synch word being interrupted by at least one bit time of quiescence of the transmitter; and at said receiver, receiving said synch word and based on a channel distortion characteristic determined for said received synch word, determining a preferred sampling point for succeeding bits of said packet. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
-
15. Within a receiver for a digital information packet, a signal acquisition analyzer configured to analyze a synch word of a header of said packet, comprising:
-
a component for synthesizing a description of a waveform of bits of said synch word, said description including a description of zero-amplitude portions of said synch word; and a component for determining an inter-symbol interference characteristic of a transmission channel, based on an analysis of a received waveform of said synch word relative to said synthesized waveform description. - View Dependent Claims (16, 17)
-
-
18. A method for transmitting and receiving a digital information packet, the method comprising the steps:
-
transmitting a synch word of a header of the packet from a transmitter to a receiver over a distorting channel, said synch word being configured to allow the receiver to acquire characteristics of a signal carrying the packet, and bits of said synch word being encoded by modulation of a carrier signal, transmission frequencies and bit transmission rates of the transmitter and receiver being approximately agreed at the beginning of the transmission, the synch word comprising a pre-agreed sequence of bits, transmission of the synch word being interrupted by at least one bit time of quiescence of the transmitter; receiving a waveform of said synch word at said receiver; comparing said received waveform to a synthesized ideal waveform of said synch word to determine a response characteristic of said channel, said comparing comprising at least one of the two steps of; convolving maid received waveform with said ideal generated waveform, and filtering said received waveform through a filter whose shape approximates a spectrum of said ideal waveform; configuring a sampling element of said receiver to sample said received waveform of the digital information packet at a preferred time, said preferred time determined relative to a maximum of said response characteristic; and
thentransmitting from the transmitter to the receiver a body of the packet, the body including information to be conveyed from the transmitter to the receiver; wherein said comparing and configuring steps at least partially overlap in time with a further step of calibrating an automatic gain control of said receiver to a power level of said received waveform.
-
Specification