Patent ID: 8964788
Filing Date: 2015-02-24
Classification: H04L,H04M

Abstract:
1. A method of controlling bidirectional data transmissions from a destination terminal in an in-band communication system, the method comprising: transmitting a start signal from the destination terminal; discontinuing transmission of the start signal upon detection of a first received signal, wherein the first received signal indicates a successful reception of the start signal from a source terminal; transmitting a negative acknowledgment (NACK) signal from the destination terminal, whereby the source terminal is constrained to respond in a first predetermined manner; discontinuing transmission of the NACK signal upon detection of a successfully received source terminal data message; transmitting an acknowledge (ACK) signal from the destination terminal, whereby the source terminal is constrained to respond in a second predetermined manner; discontinuing transmission of the ACK signal after a predetermined number of ACK signals have been transmitted; transmitting a send signal from the destination terminal; discontinuing transmission of the send signal upon detection of a second received signal, wherein the second received signal indicates a successful reception of the send signal from the source terminal; transmitting a synchronization signal from the destination terminal; transmitting a user data segment from the destination terminal using a first modulation scheme; discontinuing transmission of the user data segment upon detection of a third received signal, wherein the third received signal indicates a successful reception of the user data segment from the source terminal; and switching to a second modulation scheme if the destination terminal receives a predetermined number of a fourth received signal, wherein the fourth received signal indicates an unsuccessful reception of the user data segment from the source terminal.