A system for efficient control signaling over shared communication channels, the system comprising: a gateway configured to encode and to transmit a plurality of physical layer headers, the plurality of physical layer headers including at least a first physical layer header and a second physical layer header, wherein: the first physical layer header spans a first length and includes a first plurality of modcode partitions representing a first modcode, the first length depending on the first modcode; and the second physical layer header spans a second length and includes a second plurality of modcode partitions representing a second modcode, the second length depending on the second modcode, wherein the second length is longer than the first length; and a plurality of terminals, in wireless communication with the gateway via satellite, wherein the plurality of terminals includes at least: a first terminal configured to decode the first physical layer header and to determine the first modcode; and a second terminal configured to decode the second physical layer header and determine the second modcode, wherein the first physical layer header is of insufficient length for the second terminal to decode the first physical layer and for the second receiver to determine the first modcode associated with the first physical layer header. a gateway configured to encode and to transmit a plurality of physical layer headers, the plurality of physical layer headers including at least a first physical layer header and a second physical layer header, wherein: the first physical layer header spans a first length and includes a first plurality of modcode partitions representing a first modcode, the first length depending on the first modcode; and the second physical layer header spans a second length and includes a second plurality of modcode partitions representing a second modcode, the second length depending on the second modcode, wherein the second length is longer than the first length; and the first physical layer header spans a first length and includes a first plurality of modcode partitions representing a first modcode, the first length depending on the first modcode; and the second physical layer header spans a second length and includes a second plurality of modcode partitions representing a second modcode, the second length depending on the second modcode, wherein the second length is longer than the first length; and a plurality of terminals, in wireless communication with the gateway via satellite, wherein the plurality of terminals includes at least: a first terminal configured to decode the first physical layer header and to determine the first modcode; and a second terminal configured to decode the second physical layer header and determine the second modcode, a first terminal configured to decode the first physical layer header and to determine the first modcode; and a second terminal configured to decode the second physical layer header and determine the second modcode, wherein the first physical layer header is of insufficient length for the second terminal to decode the first physical layer and for the second receiver to determine the first modcode associated with the first physical layer header.