An example frequency converter includes a drift canceling loop with a balanced delay and a linear signal path (e.g., linear with respect to frequency scaling, amplitude modulation, and/or phase modulation). One side of the drift canceling loop includes a fixed delay, and the opposite side includes an adjustable, complementary delay. The adjustable, complementary delay facilitates precision matching of the signal delays on each side of the loop over a range of frequencies, which results in a significant improvement in noise cancelation, particularly at large offsets to the carrier, while permitting the use of a higher noise, but very fast tuning course scale oscillator. The linear signal path from the signal generator to an RF output facilitates modulation of the signal by the signal generator. A modular format is an advantageous embodiment of the invention that includes the removal of the frequency synthesizer's low phase noise reference into a separate module.

Various additional and alternative aspects are described herein. In some aspects, the present disclosure provides a method of communication by an apparatus. The method includes selecting one or more resources for transmitting data of a first data stream based on an acyclic graph. The selected resources conform to the acyclic graph comprising data streams at odd levels of the acyclic graph and resources at even levels of the acyclic graph. The acyclic graph includes edges between each level of the acyclic graph. The edges connect the resources allocated to each data stream. The method further includes transmitting the data of the first data stream on the selected one or more resources.

A wireless communication apparatus according to an embodiment includes a transceiver and a transmission slot determiner. The transceiver transmits/receives information. The transmission slot determiner determines a transmission slot in which the transceiver transmits information, from a frame time-divided into a plurality of slots, based on the rank value of self node corresponding to the number of hops to a root node. A plurality of slot groups including a plurality of continuous slots is set in the frame. The slot groups are assigned different rank values. The transmission slot determiner selects a slot group to which the rank value of self node is assigned, and determines a transmission slot from among the slots included in the selected slot group.

A multiple-access transceiver handles communications with mobile stations in environments that exceed mobile station design assumptions without necessarily requiring modifications to the mobile stations. One such environment is in Earth orbit. The multiple-access transceiver is adapted to close communications with mobile stations while exceeding mobile station design assumptions, such as greater distance, greater relative motion and/or other conditions commonly found where functionality of a terrestrial transceiver is to be performed by an orbital transceiver. The orbital transceiver might include a data parser that parses a frame data structure, a signal timing module that adjusts timing based on orbit to terrestrial propagation delays, frequency shifters and a programmable radio capable of communicating from the Earth orbit that uses a multiple-access protocol such that the communication is compatible with, or appears to the terrestrial mobile station to be, communication between a terrestrial cellular base station and the terrestrial mobile station.

Various additional and alternative aspects are described herein. In some aspects, the present disclosure provides a method of communication by an apparatus. The method includes selecting one or more resources for transmitting data of a first data stream based on an acyclic graph. The selected resources conform to the acyclic graph comprising data streams at odd levels of the acyclic graph and resources at even levels of the acyclic graph. The acyclic graph includes edges between each level of the acyclic graph. The edges connect the resources allocated to each data stream. The method further includes transmitting the data of the first data stream on the selected one or more resources.

A multiple-access transceiver handles communications with mobile stations in environments that exceed mobile station design assumptions without necessarily requiring modifications to the mobile stations. One such environment is in Earth orbit. The multiple-access transceiver is adapted to close communications with mobile stations while exceeding mobile station design assumptions, such as greater distance, greater relative motion and/or other conditions commonly found where functionality of a terrestrial transceiver is to be performed by an orbital transceiver. The orbital transceiver might include a data parser that parses a frame data structure, a signal timing module that adjusts timing based on orbit to terrestrial propagation delays, frequency shifters and a programmable radio capable of communicating from the Earth orbit that uses a multiple-access protocol such that the communication is compatible with, or appears to the terrestrial mobile station to be, communication between a terrestrial cellular base station and the terrestrial mobile station.