Low-cost noise-immune wireless methodology for demand control ventilation (DCV) Applications
First Claim
Patent Images
1. A method for sequential transmission and asynchronous reception for use in transmitting data packets from a plurality of sensors in a demand control ventilation system to a Gateway Controller, each sensor transmitting its own data packet, comprising:
- (1) sequentially transmitting a data packet from each of the plurality of sensors for a preselected transmission period at a preselected number of frequencies within a preselected frequency band by use of a narrow band Frequency Shift Key (“
FSK”
) system;
(2) tuning the Gateway controller to receive at each of the preselected number of frequencies in the preselected frequency band in an asynchronous manner wherein the Gateway controller is tuned to a particular frequency within the preselected number of frequencies for a reception period that is from approximately one-half to approximately 100% of a total transmission period required to complete step (1); and
(3) repeating steps (1) and (2) until the Gateway controller receives the first data packet from each of the plurality of sensors for a chosen interval;
(4) repeating steps (1) through (3) a preselected number of times for a chosen time period so that the Gateway controller receives a preselected number of data packets from the plurality of sensors;
wherein step (1) is repeated a preselected number of times for each of the plurality of sensors; and
wherein the data packets include information concerning carbon dioxide (“
CO2”
) concentration, humidity, temperature and a sensor identification.
0 Assignments
0 Petitions
Accused Products
Abstract
A method for reducing the cost of demand control ventilation applications deploys wireless CO2 sensors inclusive of relative humidity and temperature throughout an indoor space without the need for wiring while utilizing the license-free 902-908 MHz ISM band by use of a Sequential Transmission Asynchronous Reception System (“STARS”) that is software controlled.
8 Citations
17 Claims
-
1. A method for sequential transmission and asynchronous reception for use in transmitting data packets from a plurality of sensors in a demand control ventilation system to a Gateway Controller, each sensor transmitting its own data packet, comprising:
-
(1) sequentially transmitting a data packet from each of the plurality of sensors for a preselected transmission period at a preselected number of frequencies within a preselected frequency band by use of a narrow band Frequency Shift Key (“
FSK”
) system;(2) tuning the Gateway controller to receive at each of the preselected number of frequencies in the preselected frequency band in an asynchronous manner wherein the Gateway controller is tuned to a particular frequency within the preselected number of frequencies for a reception period that is from approximately one-half to approximately 100% of a total transmission period required to complete step (1); and (3) repeating steps (1) and (2) until the Gateway controller receives the first data packet from each of the plurality of sensors for a chosen interval; (4) repeating steps (1) through (3) a preselected number of times for a chosen time period so that the Gateway controller receives a preselected number of data packets from the plurality of sensors; wherein step (1) is repeated a preselected number of times for each of the plurality of sensors; and wherein the data packets include information concerning carbon dioxide (“
CO2”
) concentration, humidity, temperature and a sensor identification. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A method for sequential transmission and asynchronous reception for use in transmitting data packets from a plurality of sensors in a demand control ventilation system to a Gateway controller, each sensor transmitting its own data packet, comprising:
-
(1) sequentially transmitting a data packet from each of the plurality of sensors for a preselected transmission period at a preselected number of frequencies within a preselected frequency band by use of a narrow band Frequency Shift Key (“
FSK”
) system;(2) tuning the Gateway controller to receive at each of the preselected number of frequencies in the preselected frequency band in an asynchronous manner wherein the Gateway controller is tuned to a particular frequency within the preselected number of frequencies for a reception period that is from approximately one-half to approximately 100% of a total transmission period required to complete step (1); (3) repeating step (1) for each of the plurality of sensors until a confirmation signal from the Gateway controller is received by said sensor; (4) sending a confirmation signal from the Gateway controller to each of the plurality of sensors from which the Gateway controller has received the data packet; and (5) repeating steps (1) through (4) until the Gateway controller receives the first data packet from each of the plurality of sensors for a chosen interval; wherein the data packets include information concerning carbon dioxide (“
CO2”
) concentration, humidity, temperature and a sensor identification. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17)
-
Specification