Method and apparatus for transmitting and receiving encoded data using multiple frequency coding

In a communication system for networking a plurality of stations, each of which includes a transmitter and a receiver, a method for encoding a packet of data supplied by a Medium Access Control ("MAC") layer in a transmitting station that transmits said data in a series of N bursts and decoding received data units in a receiving station that receives at least one of said bursts, said method comprising the steps of:

• (a) in said transmitting station, dividing said packet into a plurality of data segments having an equal length, each having a first data byte unit and a second data byte unit;
• (b) forming at least one error correction (EC) segment from said plurality of data segments, said EC segment having an equal length with said data segments, said EC segment having a first EC byte unit that corrects errors in said first data byte units and a second EC byte unit that corrects errors in the second data byte units;
• (c) fragmenting each of said data segments and EC segments into a plurality of fragments;
• (d) for each fragment, calculating a data error control (DEC) field and including said DEC field in the segment associated with said fragment so that each segment together with its associated DEC fields defines a data unit ("DU");
• (e) transmitting said DUs in a series of N.sub.-- .sub.-- bursts;
• (f) receiving at least one of said bursts in a receiving station;
• (g) utilizing the DEC field to mark each fragment in said received bursts as one of good and bad;
• and
• (h) defining a plurality of fragment columns, each fragment column defined by like-numbered data byte units and EC byte units from said N bursts, and, for each of said fragment columns, totaling a number of good fragments, and if said number of good fragments is greater than a number (N-e) that is the minimum number of fragments necessary to reconstruct the data in the fragments of each column, then reconstructing the packet.

A communications system for a station in a network including a plurality of stations, said communications system coupled to a computer processing unit ("CPU") in the station that provides a packet of data for transmission and receives a received packet of data, said station communicating with other stations in the network utilizing a slow frequency hopping system that transmits a series of N bursts using a plurality of N frequencies and a predetermined channel sequence, said communications system comprising:

• a LAN controller including a protocol engine coupled to the CPU, said protocol engine including
• (a) segmentation means for forming said packet into at least one data segment having a first data byte unit and a second data byte unit,
• (b) segment error correction means for forming an error correction (EC) segment from said data segment, said EC segment having a first EC byte unit that corrects errors in said first data byte unit and a second EC byte unit that corrects errors in the second data byte unit;
• (c) fragmentation means for fragmenting each of said data segment and EC segment into a plurality of fragments,
• (d) DEC means for calculating a data error control (DEC) field for each fragment, and for including said DEC field in the segment associated with said fragment so that each segment together with its associated DEC fields defines a data unit ("DU"),
• (e) transmitting control means for transmitting said DUs in a series of N bursts,
• (f) receiving control means for receiving at least one of said bursts in a receiving station,
• (g) marking means utilizing the DEC field to mark each fragment in said received bursts as one of good and bad, and
• (h) reconstruction mapping means including, for each of a plurality of fragment columns defined to include a fragment from each of said N bursts, means for totaling a number of good fragments for each of said fragment columns, and if said good number is greater than a number (N-e) that is the minimum number of fragments necessary to reconstruct the data in the fragments of each column, then reconstructing the packet;
• a radio frequency (RF) modem coupled to the LAN controller, including
• a frequency synthesizer for producing a plurality of RF frequencies,
• a RF control unit coupled to the frequency synthesizer for selecting a radio frequency,
• a RF receiver,
• a RF transmitter;
• and
• an antenna coupled to said RF modem for receiving said plurality of frequencies.

A communications system for a station in a network including a plurality of stations, said communications system coupled to a computer processing unit ("CPU") in the station that provides a packet of data for transmission and receives a received packet of data, said station communicating with other stations in the network utilizing a slow frequency hopping system that transmits a series of N bursts using a plurality of N frequencies and a predetermined channel sequence, said communications system comprising:

• a LAN controller including a protocol engine coupled to the CPU, said protocol engine including
• (a) segmentation means for dividing said packet into a plurality of data segments having an equal length, each having a first data byte unit and a second data byte unit,
• (b) segment error correction means for forming at least one error correction (EC) segment from said plurality of data segments, said EC segment having an equal length with said data segments, said EC segment having a first EC byte unit that corrects errors in said first data byte units and a second EC byte unit that corrects errors in the second data byte units,
• (c) fragmentation means for fragmenting each of said data segments and EC segments into a plurality of fragments,
• (d) DEC means for calculating a data error control (DEC) field for each fragment, and for including said DEC field in the segment associated with said fragment so that each segment together with its associated DEC fields defines a data unit ("DU"),
• (e) transmission control means for transmitting said DUs in a series of N bursts,
• (f) reception control means for receiving at least one of said bursts in a receiving station,
• (g) marking means utilizing the DEC field to mark each fragment in said received bursts as one of good and bad, and
• (h) reconstruction mapping means including, for each of a plurality of fragment columns defined by like-numbered data byte units and EC byte units from each of said N bursts, means for totaling a number of good fragments for each of said fragment columns, and if said good number is greater than a number (N-e) that is the minimum number of fragments necessary to reconstruct the data in the fragments of each column, then reconstructing the packet;
• a radio frequency (RF) modem coupled to the LAN controller, including
• a frequency synthesizer for producing a plurality of RF frequencies,
• a RF control unit coupled to the frequency synthesizer for selecting a radio frequency,
• a RF receiver,
• a RF transmitter;
• and
• an antenna coupled to said RF modem for receiving said plurality of frequencies.